Renginiai

Jungtiniai Teorinės fizikos ir astronomijos seminarai

Dėl pranešimų astronomijos tematika kreiptis į vyr. m.d. Editą Stonkutę (el. p.: , tel.: +370 5 2234670, kab.: B433).

Dėl pranešimų teorinės fizikos tematika kreiptis į m.d. Algirdą Mekį (el. p.: , kab.: A433).

Informacija apie seminarus pateikiama Facebook paskyroje bei žemiau.

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Joint seminar of Institute of Theoretical Physics and Astronomy

Speaker: Thomas Halfmann, Institute of Applied Physics, Technical University of Darmstadt (Germany)

Date and time: Wednesday, 25 May 2022, 14:00 Vilnius time
Location: MSTeams meeting

Title: Stopping and storing light in a solid-state quantum memory

Coherent light-matter interactions provide powerful tools to control optical properties in quantum systems, e.g. aiming at efficient methods for optical data storage and quantum information processing. The latter rapidly developing field and applications therein require optical (quantum) memories as a key component. The talk presents implementations of coherent optical interactions in particular solids, i.e. rare-earth doped crystals. These “atom-like” solid media combine the advantages of gases (i.e. spectrally narrow transitions and long decoherence times) and solids (i.e. large storage density and scalability). In particular, the talk reports on electromagnetically induced transparency (EIT) to stop and store light pulses down to the level of single photons in a conventional doped crystal (Pr:YSO). We demonstrate performant operation of the solid memory by combination of the EIT protocol with coherence control strategies to prolong storage times by orders of magnitude up to many seconds and multi-pass approaches to boost the storage efficiency. The findings are of relevance to provide a memory for single photons and information encoded therein.

Figure: (left) Setup of magnetic coils for coherence control around the Pr:YSO memory crystal. (right) Storage of an input pulse containing in average a single photon only. Input pulse (blue data) and retrieved signal pulse (green data) vs. time.

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Įvykę seminarai

Joint seminar of Institute of Theoretical Physics and Astronomy

Speaker: Mateusz Łącki (Jagiellonian University, Kraków)

Date and time: Wednesday, 11 May 2022, 14:00 Vilnius time
Location: MSTeams meeting

Title: Dark states and bands for ultracold atoms

A proposal [Phys. Rev. Lett. 117, 233001 (2016)] to use a three-level Lambda system to create optical potentials for ultracold atoms has lead to effective lattice with subwavelength potential peaks. This potential is for atoms that occupy the dark state manifold. Recently, the proposal was extended by using bands of Hofstadter-Harper modes in Lambda system configuration. When coupled properly the three-band system hosts a dark state band, which is flat and has the Chern number, |C| > 1. Another possible extension of the original work was achieved by considering a four level atomic setup in the tripod configuration with two-dimensional dark-space with 1D motion and the presence of external gauge fields and interesting tight-binding model with long range hopping and interaction. In the talk I will present the two above extensions of the original Lambda system.

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Joint seminar of Institute of Theoretical Physics and Astronomy

Speaker: Evgeny Sherman (University of Basque Country UPV-EHU, IKERBASQUE Basque Foundation for Science, Bilbao, Spain)

Date and time: Wednesday, 27 April 2022, 14:00 Vilnius time
Location: MSTeams meeting

Title: Spintronics with random spin-orbit coupling

Spin-orbit coupling is one of the key elements of modern spintronics studying the effects of coupled charge and spin dynamics. The coupling strength is usually assumed to be independent of the electron position. Here we consider a realistic spatially random spin-orbit coupling produced, e.g., by an inevitably random distribution of dopant ions and other statistical imperfections. As demonstrated experimentally, the spin-orbit coupling is realized as a random function of coordinate correlated on a spatial scale of the order of 10 nm. We will show how to determine theoretically main properties of the random spin-orbit fields such as the variation and the correlation length. Next, we will consider the experimental consequences, where the effects of disorder are highly nontrivial. By analyzing different regimes of electron transport and spin dynamics, we will discuss the spin relaxation and various Hall effects in these structures.

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Joint seminar of Institute of Theoretical Physics and Astronomy

Speaker: Florian Schreck (University of Amsterdam)

Date and time: Wednesday, 20 April 2022, 13:30 Vilnius time
Location: MSTeams meeting

Title: Continuous Bose-Einstein condensation and superradiant clocks

Ultracold quantum gases are excellent platforms for quantum simulation and sensing. So far these gases have been produced using time-sequential cooling stages and after creation they unfortunately decay through unavoidable loss processes. This limits what can be done with them. For example it becomes impossible to extract a continuous-wave atom laser, which has promising applications for precision measurement through atom interferometry [1]. I will present how we achieve continuous Bose-Einstein condensation and create condensates (BECs) that persist in a steady-state for as long as we desire. Atom loss is compensated by feeding fresh atoms from a continuously replenished thermal source into the BEC by Bose-stimulated gain [2]. Our experiment is the matter wave analog of a cw optical laser with fully reflective cavity mirrors. The only step missing to create the long-sought continuous-wave atom laser is the addition of a coherent atom outcoupling mechanism. In addition this BEC may give us access to interesting driven-dissipative quantum phenomena over unprecedented timescales. The techniques we developed to create the continuous source of thermal atoms are also nicely suited to tackle another challenge: the creation of a continuously operating superradiant clock [3,4,5]. These clocks promise to become more rugged and/or more short-term stable than traditional optical clocks, thereby opening new application areas. In the second part of my talk I will present how we are developing two types of superradiant clocks within the European Quantum Flagship consortium iqClock [4,5].

References
[1] N. P. Robins, P. A. Altin, J. E. Debs, and J. D. Close, Atom lasers: Production, properties and prospects for precision inertial measurement, Physics Reports 529, 265 (2013).
[2] C.-C. Chen, R. González Escudero, J. Minář, B. Pasquiou, S. Bennetts, and F. Schreck, An ultracold Bose-Einstein condensate in steady state, arXiv:2012.07605 (2020).
[3] M. A. Norcia, New tools for precision measurement and quantum science with narrow linewidth optical transitions, PhD thesis, JILA, University of Colorado, Boulder, USA (2018).
[4] H. Liu, S. B. Jäger, X. Yu, S. Touzard, A. Shankar, M. J. Holland, and T. L. Nicholson, Rugged mHz-Linewidth Superradiant Laser Driven by a Hot Atomic Beam, PRL 125, 253602 (2020).
[5] H. Liu, S. B. Jäger, X. Yu, S. Touzard, A. Shankar, M. J. Holland, T. L. Nicholson, Rugged mHz-Linewidth Superradiant Laser Driven by a Hot Atomic Beam, PRL 125, 253602 (2020).

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Joint seminar of Institute of Theoretical Physics and Astronomy

Speaker: Barry Garraway (University of Sussex, UK)

Date and time: Wednesday, 13 April 2022, 14:00 Vilnius time
Location: MSTeams meeting

Title: Quantum bubbles and rings with ultra-cold atoms

The technique of radio-frequency dressing [1] allows the possibility to generate new types of traps for ultra-cold atoms. This can include different dimensionalities and different topologies such as rings, shells and toroidal surfaces. We will discuss the production and properties of these types of traps using the RF dressing technique. Full exploration of a large shell, to produce a bubble of matter-waves, or BEC, has to be performed in free-fall, i.e. in space or a drop-tower. We will show how NASA's BEC experiment in orbit (the Cold Atom laboratory [2]) can be enhanced with the use of micro-wave interactions. Diagnostic information is analysed with the free-expansion of shells and we also discuss applications to ring structures.

[1] B.M. Garraway and H. Perrin, J. Phys. B 49, 172001 (2016).
[2] R.A. Carollo et al. arXiv:2108.05880.

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Joint seminar of Institute of Theoretical Physics and Astronomy

Speaker: Özgür E. Müstecaplıoğlu (Koç University, Turkey)

Date and time: Wednesday, 6 April 2022, 14:00 Vilnius time
Location: MSTeams meeting

Title: Introduction to Quantum Thermodynamics and Its Applications

Thermodynamics fundamentally explores the relationship between energy forms and conditions on energy processes. A practical consequence of this endeavor is the systematic studies and development of so-called heat engines. Since the invention of the steam engine, the practical aspect of thermodynamics put it among the game-changing branches of science. Recently, questions of miniaturization of heat engines and the consideration of information as a form of energy have attracted much attention, which led to the emergence of the rapidly developing field of quantum thermodynamics. This talk will briefly introduce the basics of quantum thermodynamics and its potential applications, ranging from quantum information engines to quantum thermal diodes and transistors.

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Joint seminar of Institute of Theoretical Physics and Astronomy

Speaker: Dr. Guillaume Guiglion, Leibniz-Institut für Astrophysik Potsdam

Date and time: Tuesday, 5 April 2022, 11:00-12:00 Vilnius time
Location: MSTeams meeting

Title: The puzzling origin of lithium in the era of large spectroscopic surveys

The chemical evolution of lithium in the Milky Way represents a major problem in modern astrophysics. Indeed, the lithium we use in our everyday life (for instance in cellphone batteries) was synthesized during the Big Bang, as well as during specific stages of stellar evolution, such as the supernovae and red-giant branch phases. Understanding the chemical evolution of lithium in our Galaxy is then a complex puzzle that astronomers try to solve. In this colloquium, I will discuss on the current methods used to solve this puzzle, in particular the use of stellar spectroscopy, and machine-learning.

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Joint seminar of Institute of Theoretical Physics and Astronomy

Speaker: Nathan Goldman (Université libre de Bruxelles)

Date and time: Wednesday, 30 March 2022, 14:00 Vilnius time
Location: MSTeams meeting

Title: Orbital order and chiral currents of interacting bosons with π-flux

Higher Bloch bands provide a remarkable setting for realizing many-body states that spontaneously break time-reversal symmetry, offering a promising path towards the realization of interacting topological phases. Here, we propose a different approach by which chiral orbital order effectively emerges in the low-energy physics of interacting bosons moving on a square plaquette pierced by a π-flux. We analyze the low-energy excitations of the condensate in terms of two orbital degrees of freedom and identify a gapped collective mode corresponding to the out-of-phase oscillations of the relative density and phase of the two orbitals. We further highlight the chiral nature of the ground state by revealing the cyclotron-like dynamics of the density upon quenching an impurity potential on a single site. Our single-plaquette results can be used as building blocks for extended dimerized lattices, as we exemplify using the BBH model of higher-order topological insulators. Our results provide a distinct direction to realize interacting orbital-like models that spontaneously break time-reversal symmetry, without resorting to higher bands nor to external drives.

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Joint seminar of Institute of Theoretical Physics and Astronomy

Speaker: Ulrich Schneider (University of Cambridge)

Date and time: 23 March 2022, 14:00 Vilnius time
Location: MSTeams meeting

Title: Realizing a first order quantum phase transitions in a driven optical lattice

Phase transitions and critical phenomena have been at the heart of many-body physics, and quantum simulations with cold atoms from the beginning. While almost all phase transitions in cold atoms systems are continuous, there is a renewed interest also in discontinuous (first-order) phase transitions and the quantum metastability, whose relativistic analogues are believed to play an important role in early-universe cosmology (false vacuum decay).

We experimentally demonstrate a novel level of control over a quantum phase transition by combining an optical lattice with an uncommon type of Floquet engineering based on a resonant drive. Contrary to most applications of periodic driving, where the drive frequency is selected to avoid all resonances, we resonantly couple the lowest two bands of a lattice. With this drive, we can not only induce the superfluid to Mott insulator transition but are furthermore able to control its character and turn the Mott transition from a continuous into a discontinuous transition, thereby opening the door to quantum simulations of the early universe and interacting topological transitions in condensed matter systems.

In the last part of the talk I will in addition give an update on our work on optical quasicrystals. Quasicrystals are a novel form of condensed matter that is not periodic, but nonetheless long-range ordered. They can be described by self-similar, fractal tilings containing more than one type of unit cell, such as the celebrated Penrose tiling. Many foundational concepts of periodic systems such as Blochwaves or Brillouin zones are not applicable to quasicrystals, thereby giving rise to new physics.

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 Joint seminar of Institute of Theoretical Physics and Astronomy

Speaker: David Wilkowski (MajuLab, Centre for Quantum Technologies)

Date and time: Wednesday, 16 March 2022, 14:00 Vilnius time
Location: MSTeams meeting

Title: Simulation of artificial non-Abelian Gauge fields using an ultracold gas

Abstract: Gauge fields are of key importance in modern quantum theory where they represent the gauge bosonic fields. For non-commutative symmetry groups, the gauge field is non-Abelian. In this talk, I will explain how artificial non-Abelian gauge fields can be generated in an ultracold gas using atom-light interactions. I will then give several examples where we emphasize on specific properties of these non-Abelian gauge fields. As a first example, I will discuss close-loop transformations, which depend on the initial point in sharp contrast with the classical Gauss-Bonnet theorem. I will follow on the wave-packet non-inertial dynamic in homogenous non-Abelian gauge. Finally, I will present recent experiments where we realized an atomtronics spin field effect transistor.

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Joint seminar of Institute of Theoretical Physics and Astronomy

Speaker: Prof. Päivi Törmä (Aalto University, Helsinki, Finland)

Date and time: Wednesday, 9 March 2022, 14:00 Vilnius time
Location: MSTeams meeting

Title: Quantum geometry and topology in superconductors and superfluids

Superconductivity, superfluidity and Bose-Einstein condensation (BEC) are many-body phenomena where quantum statistics are crucial and the effect of interactions may be intriguing. Superconductors are already widely applied, but theoretical understanding of superconductivity and condensation in several real-world systems is still a challenge, and superconductivity at room temperature remains a grand goal. We have discovered that superconductivity (superfluidity) has a connection to quantum geometry [1]. Namely, the superfluid weight in a multiband system has a previously unnoticed component which we call the geometric contribution. It is proportional to the quantum metric of the band. Quantum metric is connected to the Berry curvature, and this allows to relate superconductivity with the topological properties of the band. Using this theory, we have shown that superconductivity is possible also in a flat band where individual electrons would not move. We and other groups have shown [2] that these results are essential in explaining the observation of superconductivity in bilayer graphene and may eventually help realize superconductors at elevated temperatures [3]. Recently, we have shown that quantum geometry can enhance also light-matter coupling [4], and quantum correlations of a weakly interacting Bose-Einstein condensate [5].

[1] S. Peotta, P. Törmä, Nature Commun. 6, 8944 (2015); A. Julku, S. Peotta, T.I. Vanhala, D.-H. Kim, P. Törmä, Phys. Rev. Lett. 117, 045303 (2016); P. Törmä, L. Liang, S. Peotta, Phys. Rev. B 98, 220511(R) (2018)
[2] A. Julku, T.J. Peltonen, L. Liang, T.T. Heikkilä, P. Törmä, Phys. Rev. B 101, 060505(R) (2020); X. Hu, T. Hyart, D.I. Pikulin, E. Rossi, Phys. Rev. Lett. 123, 237002 (2019); F. Xie, Z. Song, B. Lian, B.A. Bernevig, Phys. Rev. Lett. 124, 167002 (2020); for a news article see L. Classen, Physics 13, 23 (2020)  https://physics.aps.org/articles/v13/23
[3] P. Törmä, S. Peotta, B.A. Bernevig, Superfluidity and quantum Geometry in twisted multilayer systems (review article), arXiv:2111.00807 (2021)
[4] G. Topp, C.J. Eckhardt, D.M. Kennes, M.A. Sentef, P. Törmä, Phys. Rev. B 104, 064306 (2021)
[5] A. Julku, G.M. Bruun, P. Törmä, Phys. Rev. Lett. 127, 170404 (2021)

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Joint seminar of Institute of Theoretical Physics and Astronomy

Speaker: Victor Galitski (Joint Quantum Institute, University of Maryland)

Date and time: Wednesday, 2 March 2022, 14:00 Vilnius time
Location: MSTeams meeting

Title: Many-body dynamical localization

The kicked rotor system is a textbook example of how classical and quantum dynamics can drastically differ. The energy of a classical particle kicked periodically will increase linearly in time whereas in the quantum version the energy saturates after a finite number of kicks - a phenomenon of dynamical localization that has been observed in cold atom experiments. On the theory side, its explanation hinges on Anderson localization in the angular-momentum space. Conventional wisdom says that in a many-particle system with short-range interactions the localization will be destroyed due to the coupling of widely separated momentum states. This talk will explore the question of whether dynamical localization can persist in interacting systems. Both theoretical [1] and experimental [2] results will be presented.

References:
[1] C. Rylands, E. Rozenbaum, V. Galitski, and R. Konik, Phys. Rev. Lett. 124, 155302 (2020)
[2] A. Cao et al., https://arxiv.org/abs/2106.09698

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 Joint seminar of Institute of Theoretical Physics and Astronomy

Speaker: Nir Davidson (Weizmann Institute of Science, Rehovot, Israel)
Date and time: Wednesday, 9 February 2022, 14:00 Vilnius time 
Location: MSTeams meeting

Title: Simulating spin Hamiltonians and solving computational problems with coupled lasers

Computational problems may be solved by realizing physics systems that can simulate them. Here we present a new system of up to >1000 coupled lasers that is used to solve hard computational tasks. The well-controlled dissipative coupling anneals the lasers into a stable phase-locked state with minimal loss, that can be mapped on different computational minimization problems. We demonstrate this ability for simulating XY spin systems and finding their ground state, for phase retrieval, for imaging through scattering medium and more.

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Joint seminar of Institute of Theoretical Physics and Astronomy

Speaker: Wen-Te Liao (National Central University Taiwan)
Date and time: Thursday, 27 January 2022, 14:00 Vilnius time
Location: MSTeams meeting

Title: Synthetic Gauge Potentials for the Dark State Polaritons in Atomic Media

Abstract: The quest of utilizing neutral particles to simulate the behaviour of charged particles in a magnetic field makes the generation of the artificial magnetic field of great interest. We put forward an optical scheme to generate effective gauge potentials for stationary-light polaritons in the static laboratory frame. To demonstrate the capabilities of our approach, we present a recipe for having dark-state polaritons in degenerate Landau levels. Our scheme paves a novel way towards a versatile quantum simulator for mimicking different Hamiltonians by electromagnetically induced transparency.

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Joint seminar of Institute of Theoretical Physics and Astronomy

Speaker: Marco Di Liberto (Institute for Quantum Optics and Quantum Information, Innsbruck)
Date and time: Wednesday, 15 December 2021, 14:00 Vilnius time
Location: MSTeams meeting

Title: Exploring topological effects in interacting systems of ultracold atoms

ABSTRACT: The investigation of topological systems with ultracold atoms has witnessed a remarkable progress over the last decade. Several achievements concerning the design and characterization of topological bands have shown full control at the single-particle level. More recently, novel directions towards the realization of many-body topological states have already reached some important milestones. Here, I will discuss several topological effects that can be studied with ensembles of few- or many- particle systems of ultracold atoms. I will show how topology appears in lattice bound states of two particles, I will discuss how arrays of dipolar atoms can be used to design a rich landscape of topological states and I will then present a mechanism to spontaneously obtain chiral currents that exploits local interactions in the presence of \pi-flux without externally driving the system.

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Joint seminar of Institute of Theoretical Physics and Astronomy

Speaker: Leticia Tarruell, ICFO-The Institute of Photonic Sciences, Castelldefels (Barcelona), Spain
Date and time: Wednesday, 1 December 2021, 14:00 Vilnius time
Location: MSTeams meeting

Title: Realizing a one-dimensional topological gauge theory in an optically dressed Bose-Einstein condensate

Quantum gases constitute a versatile testbed for exploring the behaviour of quantum matter subjected to electric and magnetic fields. While most experiments consider classical gauge fields that act as a simple static background for the atoms, gauge fields appearing in nature are instead quantum dynamical entities that are influenced by the spatial configuration and motion of matter, and that fulfil local symmetry constraints. In my talk, I will discuss our recent realization of a chiral BF theory: a topological gauge theory for linear anyons that corresponds to a possible one-dimensional reduction of the Chern-Simons gauge theory effectively describing fractional quantum Hall systems [1-3]. By using the local symmetry constraint of the theory, we encode the gauge field in terms of the matter field. The result is a system with chiral interactions, which we engineer in a potassium Bose-Einstein condensate by synthesizing optically dressed atomic states with a momentum-dependent scattering length. When this dependence is linear, matter behaves as if minimally coupled to a density-dependent vector potential. Theoretically, we show that the system then realizes the chiral BF Hamiltonian at the quantum level. Experimentally, we observe its two main features: the formation of chiral bright solitons - self-bound states of the matter field that only exist when propagating in one direction – and the back-action of matter into the gauge field. Our results establish chiral interactions as a novel resource for quantum simulation experiments with ultracold atoms and pave the way towards implementing topological gauge theories in higher dimensions [4].

[1] S. J. B. Rabello, Phys. Rev. Lett. 76, 4007 (1996).
[2] U. Aglietti, L. Griguolo, R. Jackiw, S.-Y. Pi, and D. Seminara, Phys. Rev. Lett. 77, 4406 (1996).
[3] M. J. Edmonds, M. Valiente, G. Juzeliūnas, L. Santos, and P. Öhberg, Phys. Rev. Lett. 110, 085301 (2013).
[4] G. Valentí-Rojas, N. Westerberg, and P. Öhberg, Phys. Rev. Research 2, 033453 (2020).

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Joint seminar of Institute of Theoretical Physics and Astronomy

Speaker: PhD Edoardo Lagioia (Dipartimento di Fisica e Astronomia "Galileo Galilei", Università di Padova)
Date and time: December 8, 11:00, 2021
Location: D401, Sauletekio av. 3. Vilnius & MSTeams meeting

Title: Multiple stellar populations in globular clusters of the Local Group

The discovery of multiple stellar populations (MPs) in globular clusters (GCs) represents a game-changing result in modern stellar astrophysics.
The ever-growing evidence of unexpected chemical and dynamic properties of MPs raises several questions about how GCs formed and the role they played in the assembly and evolution of the host galaxies.
A systematic study of incidence and extension of MPs in a large sample of GCs in the Local Group has been undertaken in the last decade, thanks to the availability of a huge database of multi-wavelength observations collected by the Hubble Space Telescope.
I will present a short review of the latest results coming from the study of MPs across the evolutionary stages of stars in GCs, with a focus on helium enrichment and its implications on the different scenarios assumed for the origin of MPs.

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Joint seminar of Institute of Theoretical Physics and Astronomy

Speaker: Michael Fleischhauer (Dept. of Physics & reserach center OPTIMAS, Univ. of Kaiserslautern, Germany)
Date and time: Wednesday, 24 November 2021, 14:00 Vilnius time
Location: MSTeams meeting

Title: Topology of mixed states

Topological states of matter have fascinated physicists since a long time. The notion of topology is however usually associated with ground states of (many-body)-Hamiltonians, which are pure. So what is left of it at finite temperatures and can topological protection be extended to non-equilibrium steady states (NESS) of open systems? Can suitable observables be constructed that preserve the integrity of topological invariants for mixed states and what are measurable consequences of their existence? Can we classify the topology of finite-temperature and NESS using generalized symmetries? Motivated by topological charge pumps, first introduced by Thouless, I will first discuss a topological invariant for systems that break time reversal symmetry based on the many-body polarization, called ensemble geometric phase (EGP) [1]. In contrast to charge transport, the EGP can be used to probe topology in one dimensional non-interacting [2] and interacting [3], closed and open systems alike. Furthermore different from other constructions, such as the Uhlmann phase, it can be extended to two dimensions [4]. I will then extend the definition to systems with time-reversal symmetry [5] and finally talk about measurable consequences of mixed-states topological invariants.
[1] C.E. Bardyn, L. Wawer, A. Altland, M. Fleischhauer, S.Diehl, (PRX 2018)
[2] D. Linzner, L. Wawer, F. Grusdt, M. Fleischhauer, (PRB 2016)
[3] R. Unanyan, M. Kiefer-Emmanouilidis, M. Fleischhauer, (PRL 2020)
[4] L. Wawer, M. Fleischhauer, (PRB 2021)
[5] L. Wawer, M. Fleischhauer, arxiv:2109.01487

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Joint seminar of Institute of Theoretical Physics and Astronomy

Speaker: Gershon Kurizki (Weizmann Institute, Israel)
Date and time: Wednesday, 17 November 2021, 14:00 Vilnius time
Location: MSTeams meeting

Title: From Quantum Mechanics to Thermodynamics and Back: On Quantum Systems, Baths and Observers

Thermodynamics requires a system to equilibrate with its thermal environment, alias a bath. However, our results over the years have shown that, surprisingly, nonintrusive observations of a quantum system may heat or cool it, thus preventing the equilibration [1,2]. Recently, we have shown that also the bath state, which is considered immutable in thermodynamics, is dramatically changed by a quantum probe and its observations [3]. These effects stem from the unavoidable entanglement between quantum systems and baths even when they are weakly coupled, thus undermining the tenets of thermodynamics in the quantum domain. Most remarkably, we have recently demonstrated that probe observations can render thermal bath states nearly pure [4]. The implications are far reaching, most prominently the ability to reverse the time arrow of the entire system-bath compound, by causing its quantum coherent oscillation. This raises the question: Is thermodynamics, which rests on the concept of a bath, compatible with quantum mechanics? It may appear necessary to assume that a quantum working medium in a heat machine is dissipated by a bath [5,6]. Yet, most recently, we have shown that heat machines can be perfectly coherent, non-dissipative devices realized by nonlinear interferometers fed by few thermal modes [7], so that baths are redundant. Finally, I will discuss the ability of observers to commute information to work [8] and speculate on the role of observers in physics [9].

References to our work:

1. Nature 452, 724 (2008).
2. PRL 105,160401 (2010).
3. NJP 22, 083035 (2020).
4. Arxiv 2108.09826 (2021)
5. Nat. Commun. 9, 165 (2018).
6. PNAS 115, 9941 (2018); PNAS 114, 12156 (2017).
7. Arxiv2108.10157 (2021).
8. PRL 127, 040602 (2021).
9. G.Kurizki and G. Gordon, “The Quantum Matrix” (Oxford Univ. Press, 2020).

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Joint seminar of Institute of Theoretical Physics and Astronomy

Speaker: Alessio Celi (Autonomous University of Barcelona)
Date and time: Wednesday, 10 November 2021, 14:00 Vilnius time
Location: MSTeams meeting

Title: Strategies for simulating gauge theories with NISQ machines

Abstract: Gauge theories represent a fierce challenge and an amazing opportunity for quantum simulation. Up to date, proof-of-principle experiments have been limited to gauge theories in one spatial dimension. In this talk, I will focus on three key problems encountered in simulating gauge theories beyond one spatial dimension: I) the realization of magnetic interactions, II) the ability to “take the continuum limit” with finite resources, and III) the preparation of a targeted state. To exemplify such problems, I will consider spin ice and Kogut-Susskind U(1) gauge theory in two dimensions as relevant examples in condensed matter and particle physics, respectively. I will present solutions that apply to current and near-term atomic quantum simulators in terms of I) a dual formulation of the theory that exploits Rydberg blockade interactions [1], II) a proper definition of the magnetic basis [2], and III) a variational preparation of the ground state [3].

[1] AC, B. Vermersch, O. Viyuela, H. Pichler, M.D. Lukin, P. Zoller, “Emerging Two-Dimensional Gauge Theories in Rydberg Configurable Arrays”, Phys. Rev. X 10, 021057 (2020).
[2] J.F. Haase, L. Dellantonio, AC, D. Paulson, A. Kan, K. Jansen, C.A. Muschik, “A resource efficient approach for quantum and classical simulations of gauge theories in particle physics”, Quantum 5, 393 (2021).
[3] D. Paulson, L. Dellantonio, J. F. Haase, AC, A. Kan, A. Jena, C. Kokail, R. van Bijnen, K. Jansen, P. Zoller, C.A. Muschik, “Towards simulating 2D effects in lattice gauge theories on a quantum computer”, Phys. Rev. X Quantum 2 (3), 030334 (2021).

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Joint seminar of Institute of Theoretical Physics and Astronomy

Speaker: Piotr Deuar (Institute of Physics, Polish Academy of Sciences, Warsaw, Poland)
Date and time: Wednesday, 20 October 2021, 14:00 Vilnius time
Location: MSTeams meeting

Title: Simulating the complete quantum dynamics of very large systems using phase-space sampling

The quantum dynamics of macroscopic systems is obviously a well known difficult problem because the quantum configuration space grows exponentially with system size. However, it turns out that under the right conditions it can be mastered using appropriately noisy trajectories of a random sample of nonorthogonal quantum states. This is the so-called phase-space approach. I will talk about the basics of the approach for the "positive-P" phase-space distribution. The computational difficulty of a positive-P treatment is found to grow merely linearly or log-linearly with system size .... but with a nasty caveat. What then are the required conditions for the technique to work? A recent study [1] found the regimes of applicability for dissipative Bose-Hubbard models which are used to describe e.g. lattices of coupled optical cavities, self-organization in an optical cavity, or polaritons confined to arrays of micropillars. With sufficient (but not overwhelming) dissipation we were able to demonstrate e.g. a full quantum treatment of a nonuniform two-dimensional system with tens of thousands of sites, larger than any contemporary experimental setups.

[1] P. Deuar, A. Ferrier, M. Matuszewski, G. Orso, M. H. Szymanska, Fully Quantum Scalable Description of Driven-Dissipative Lattice Models, PRX Quantum 2, 010319 (2021).

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Joint seminar of Institute of Theoretical Physics and Astronomy

Speaker: Jakub Zakrzewski (Jagiellonian University, Krakow)
Date and time: Wednesday, 13 October 2021, 14:00 Vilnius time
Location: MSTeams meeting

Title: Does many-body localization exist?

Abstract: I will describe our recent attempts to answer the question posed in the title. I will concentrate on a simple paradigmatic model of a disordered Heisenberg chain with random or quasiperiodic disorder.

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Joint seminar of Institute of Theoretical Physics and Astronomy

Speaker: Gyu-Boong Jo (Department of Physics, HKUST)
Date and time: Wednesday, 29 September 2021, 14:00 Vilnius time
Location: MSTeams meeting

Title: Non-Hermitian spin-orbit-coupled quantum gases

While spin-orbit coupling (SOC), an essential mechanism underlying quantum phenomena from the spin Hall effect to topological insulators, has been widely studied in well-isolated Hermitian systems, much less is known when the dissipation plays a major role in spin-orbit-coupled quantum systems. I will report the realization of the non-Hermitian spin-orbit-coupled quantum gases and observation of a parity-time (PT ) symmetry- breaking transition as a result of the competition between SOC and dissipation. In our experiment, tunable dissipation, introduced by state-selective atom loss, enables the energy gap, opened by SOC, to be engineered and closed at the critical dissipation value, the so-called exceptional point (EP) . The realized EP of the non-Hermitian band structure exhibits chiral response when the quantum state changes near the EP. This topological feature enables us to tune SOC and dissipation dynamically in the parameter space, and observe the state evolution is direction- dependent near the EP, revealing chiral spin transfer between different quantum states when the quantum state encircles the EP. This topological control of quantum state for non-Hermitian fermions provides new methods of quantum control, and also sets the stage for exploring non-Hermitian topological states with SOC.
More details are available in a recent article: https://arxiv.org/abs/2106.04874

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Joint seminar of Institute of Theoretical Physics and Astronomy

Pranešėjas: Sergejus Orlovas (FTMC)
Data ir laikas: ketvirtadienis, 17 birželio 2021, 14:00
Vieta: MSTeams susitikimas

Pavadinimas: Optinio vektorinio židinio inžinerija ir jos taikymai

Fundamentalios lazerinio rezonatoriaus modos yra plačiai žinomos ir taikomos nuo pat koherentinių šaltinių atsiradimo. Plačių taikymų dėka yra gerai žinomi jų privalumai, tuo pačiu ir trūkumai. Prasta raiška ir skyra vaizdinime, difrakcinis ir dispersinis plitimas, prasta lokalizacija, ribotas fotono laisvės laipsnių skaičius ir t.t. Visos šios standartinių (Lagero-Gauso bei Hermito-Gauso) modų problemos yra sprendžiamos optinio vektorinio židinio inžinerijos metodais, kurių dėka struktūrinė šviesa pagerina raišką, priešinasi difrakcijai ir dispersijai, užtrikrina super-rezoliuciją bei atranda naujus egzotinius šviesos darinius.

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Joint seminar of Institute of Theoretical Physics and Astronomy

Speaker: Ian B. Spielman (National Institute of Standards and Technology and the University of Maryland)
Date and time: Tuesday, 15 June 2021, 14:00 Vilnius time
Location: MSTeams meeting

Title: Floquet-engineering near-perfect Dirac bands

Over the years my group has performed a number of experiments realizing relativistic physics using cold atoms — described by the 1D Dirac Hamiltonian in some degree of approximation. I will begin by reviewing these results in conjunction with those from the whole of the cold-atom community.

With that backdrop, I describe a spin dependent bipartite Floquet lattice, in which the dispersion relation is linear for all points in the Brillouin zone. The (stroboscopic) Floquet spectrum of our periodically-driven Hamiltonian features perfect spin-momentum locking, a linear Dirac dispersion, and unidirectional spin-motion.

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Joint seminar of Institute of Theoretical Physics and Astronomy

Speaker: Thomas Busch (Okinawa Institute of Science and Technology Graduate University)
Date and time: Tuesday, 8 June 2021, 14:00 Vilnius time
Location: MSTeams meeting

Title: Magnetometry with Bose-Einstein condensates

Atomic Bose-Einstein condensates are highly controllable matter waves that can be used to create advanced metrological schemes. In this presentation I will show how a composite light-matter magnetometer can be constructed using a transversely driven multi-component Bose-Einstein condensate coupled to two distinct electromagnetic modes of a linear cavity. Above the critical pump strength, the change of the population imbalance of the condensate caused by an external magnetic field entails the change of relative photon number of the two cavity modes and monitoring the cavity output fields allows for nondestructive measurement of the magnetic field in real time.

The sensitivity of the proposed magnetometer exhibits Heisenberg-like scaling with respect to the atom number and for state-of-the-art experimental parameters the lower bound on the sensitivity of such a magnetometer can be shown to be of the order of fT/Hz^(-1/2) - pT/Hz^(-1/2) for typical experimental parameters.

Cavity-enhanced magnetometer with a spinor Bose–Einstein condensate K. Gietka, F. Mivehvar, and Th. Busch New J. Phys. 23 043020 (2021)

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Joint seminar of Institute of Theoretical Physics and Astronomy

Speaker: Hannah Price (University of Birmingham)
Date and time: Tuesday, 1 June 2021, 14:00 Vilnius time
Location: MSTeams meeting

Title: Simulating quantum models with classical-mechanical metamaterials

Metamaterials based on mechanical elements have been developed over the past decade as a powerful platform for exploring analogs of electron transport in exotic regimes that are hard to realize in real materials. The control afforded over such acoustic and mechanical metamaterials is also opening up new directions for controlling the transport of sound and energy. In this seminar, I will discuss how to simulate desired quantum Hamiltonians with classical mechanical systems of pendulum by exploiting the rotating-wave approximation. I will present recent experimental progress towards engineering interacting and non-reciprocal Hamiltonians in a system of two oscillators, and discuss ways in which this approach may be extended to realize topological models. This opens doors towards the simulation of exotic lattice models and the combined exploration of topological physics, non-Hermiticity, and nonlinear dynamics.

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Joint seminar of Institute of Theoretical Physics and Astronomy

Speaker: Emmanuel Paspalakis (Materials Science Department, School of Natural Sciences, University of Patras, Patras, Greece)
Date and time: Tuesday, 25 May 2021, 14:00 Vilnius time
Location: MSTeams meeting

Title: Quantum Interference and Coherence Effects in Quantum Emitters near Nanophotonic Structures

A quantum emitter placed near a nanophotonic structure may significantly alter its spontaneous emission. This happens as the nanophotonic structure modifies the electromagnetic density of modes seen by the quantum emitter. In the weak coupling light-matter interaction regime, this leads to either enhanced or suppressed spontaneous emission decay rates via the Purcell effect and to exponential decay of an excited two-level quantum emitter. For strong light-matter coupling of a quantum emitter with the nanophotonic structure, coherent oscillatory energy exchange between the quantum emitter and the photonic environment occurs which may result in reversible spontaneous emission dynamics.

Besides two-level quantum emitters, important quantum coherence and interference effects occur in three-level quantum emitters. In particular, in the V-type quantum emitter, one may simulate quantum interference effects in spontaneous emission by placing the quantum emitter in a photonic environment with an anisotropic Purcell effect. The quantum interference in spontaneous emission allows for coupling between the two upper states of the V-type emitter in the anisotropic vacuum while, in the ordinary vacuum, no coupling occurs. This phenomenon has been explored mainly in the weak light-matter regime, next to several nanophotonic structures, including metamaterials and their structures, plasmonic nanostructures, and semiconductor microcavities. Quantum interference in spontaneous emission leads to strongly enhanced quantum and nonlinear optical phenomena and may be used for the enhancement of the power generated by a photovoltaic device.

In this presentation, we outline the main ideas for simulating quantum interference in spontaneous emission in a quantum emitter near a nanophotonic structure and present results obtained from our group using different nanophotonic structures (mainly metallic or metal-dielectric nanostructures but also nanostructures made from two-dimensional materials) in the weak and strong light-matter regime. We also show some examples of modifying and controlling quantum coherence optical phenomena using the created quantum interference in spontaneous emission.

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Joint seminar of Institute of Theoretical Physics and Astronomy

Speaker: Verónica Ahufinger (Department of Physics, Universitat Autònoma de Barcelona)
Date and time: Tuesday, 18 May 2021, 14:00 Vilnius time
Location: MSTeams meeting

Title: Ultracold atoms carrying orbital angular momentum in lattices of rings: topology and quantum magnetism

In this talk, we will discuss the physics of ultracold atoms carrying Orbital Angular Momentum (OAM) in lattices of ring potentials in the single-particle and in the Mott insulator limits. In the former limit, we find topologically protected edge states. In the latter limit, we show that the system can realize a variety of spin-1/2 models, including the XYZ Heisenberg model with or without external field.

In the context of topology, we study the single-particle properties of a system formed by ultracold atoms loaded into the manifold of l=1 OAM states of an optical lattice with a diamond chain geometry [1,2]. Through a series of successive basis rotations, we show that the OAM degree of freedom induces phases in some tunneling amplitudes of the tight-binding model that are equivalent to a net flux through the plaquettes and give rise to a topologically non-trivial band structure and protected edge states. In addition, we demonstrate that the system also exhibits Aharanov-Bohm caging. In two dimensional (2D) lattices, we also propose a realization of a 2D high order topological insulator [3]. We describe the system in terms of two decoupled lattice models, each of them displaying one-dimensional edge states and zero-dimensional corner states that are correlated with the topological properties of the bulk. We show that this topologically non-trivial regime can be explored in a wide range of experimentally feasible values of the parameters of the physical system. Furthermore, we propose an alternative way to characterize the second-order topological corner states based on the computation of the Zak's phases of the bands of first-order edge states.

In the Mott insulator limit, we focus on unit filling, where each trap is occupied by a single atom and a direct mapping between the OAM and spin-1/2 states can be performed [4]. We consider explicitly the dependence of the effective couplings on the geometry of the system and demonstrate that several models of interest related to a general XYZ Heisenberg model with external field can be obtained. Furthermore, we discuss how the relative strength of the effective couplings can be tuned and which phases can be explored by doing so in realistic setups.

[1] G. Pelegrí, A. M. Marques, R. G. Dias, A. J. Daley, V. Ahufinger and J. Mompart, Topological edge states with ultracold atoms carrying orbital angular momentum in a diamond chain. Phys. Rev. A 99, 023612 (2019).
[2] G. Pelegrí, A. M. Marques, R. G. Dias, A. J. Daley, J. Mompart and V. Ahufinger, Topological edge states and Aharanov-Bohm caging with ultracold atoms carrying orbital angular momentum. Phys. Rev. A 99, 023613 (2019)
[3] G. Pelegrí, A. M. Marques, V. Ahufinger, J. Mompart, and R. G. Dias, Second-order topological corner states with ultracold atoms carrying orbital angular momentum in optical lattices, Phys. Rev. B 100, 205109 (2019).
[4] G. Pelegrí, J. Mompart, V. Ahufinger, A. J. Daley, Quantum magnetism with ultracold bosons carrying orbital angular momentum, Phys. Rev. A 100, 023615 (2019).

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Joint seminar of Institute of Theoretical Physics and Astronomy

Pranešėjas: Kęstutis Staliūnas (Katalonijos Technikos Universitetas (Universitat Politecnica Catalunya – UPC), Vilniaus Universitetas (Lazerių Tyrimų Centras))
Data ir laikas: antradienis, 11 gegužės, 2021 m., 14:00 val.
Vieta: MSTeams susitikimas

Pavadinimas: Šviesos dariniai mikrolazeriuose, ir jų valdymas fotoniniais kristalais

Lazeriuose skersinė šviesos dinamika labai primena kondensuotų atomų dinamiką magnetinėse gaudyklėse. Paraboliniai veidrodžiai lazeriuose matematiškai atitinka parabolinį gaudyklės potencialą. Šviesos sklidimo lygtis labai primena Šredingerio lygtį banginei funkcijai. Skersinės modos lazeriuose visai analogiškos gaudyklės modoms. Pagrindinis skirtumas tik kad lazeriuose mes natūraliai turime ir koherentinio stiprinimo – bozonų dauginimo – mechanizmą, kurį sunku realizuoti atomų kondensatuose.

Papasakosiu apie lazerių, kuriuos tyrinejame tiek Technikos Universitete Katalonijoje, tiek Lazerių Tyrimo Centre Lietuvoje, šviesos dinamiką, beigi pagrindinius būdus manipuliuoti ta šviesa. Dažniausiai tam naudojame vadinamus fotoninius kristalus, kurie šviesą sutvarko, taip sakant sukondensuoja į žemiausią gaudyklės modą. Atomų kondensatuose panašius triukus būtų galima išdarinėti su dinaminėmis gardelėmis, na blyksinčiomis gardelėmis, kai kas jas vadina laikiniais kristalais.

Žodžiu papasakosiu apie šviesos valdymą mikrolazeriuose, ir kartu pagalvosime ar būtų galima pritaikyti panašius triukus šaltų atomų kondensatuose.

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Joint seminar of Institute of Theoretical Physics and Astronomy

Speaker: Jordi Mompart (Department of Physics, Universitat Autònoma de Barcelona)
Date and time: Tuesday, 4 May 2021, 14:00 Vilnius time
Location: MSTeams meeting

Title: Supersymmetry and topology in coupled optical waveguides

The integration of all basic components for the generation, manipulation and detection of light on optical chips is driving scientific and technological advances, e.g. in the development of information technology and data communications, sensing devices or quantum technologies. Moreover, because of their flexibility, scalability and the possibility to directly observe the evolution of the wave function by means of simple imaging techniques, integrated photonic structures are an ideal playground for quantum simulation, i.e. to emulate quantum phenomena that appear in other branches of physics. Moreover, these quantum-optical analogies also allow the design of novel integrated photonic circuits with exceptional properties. In this context, we exploit the non-trivial properties derived from quantum physics to design new integrated photonic devices with advanced functionalities and enhanced performances, as well as to design new photonic simulators. In particular, we exploit the similarity between the Helmholtz and Schrödinger equations, which allows to mimic the temporal dynamics of a single particle trapped in a lattice potential with the spatial evolution of a light beam propagating in a set of optical waveguides, to apply supersymmetric transformations (SUSY), adiabatic passage processes and nontrivial topological geometries to coupled optical waveguide systems.

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Joint seminar of Institute of Theoretical Physics and Astronomy

Speaker: Sonja Franke-Arnold (Glasgow Unversity)
Date and time: Friday, 30 April 2021, 14:00 Vilnius time
Location: MSTeams meeting

Title: Vectorial light matter interaction

Research on complex vector light has seen an explosion in activity over the past decades, powered by technological advances for generating such light, and driven by questions of fundamental science as well as engineering applications.
Yet, when it comes to light-matter interaction we often ignore the role of polarisation. I will present the methods we use to generate and analyse vector light in our lab, discuss the interplay between vector light, external magnetic fields and atomic vapours, and show how we detect magnetic field alignment with spin aligned atoms.

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Joint seminar of Institute of Theoretical Physics and Astronomy

Speaker: Maciej Lewenstein (The Institute of Photonic Sciences, Barcelona)
Date and time: Thursday, April 15 at 14:00 Vilnius time
Location: MSTeams meeting

Title: A cold-atom approach to topological quantum matter across the energy scale

The universal quantum computers with large number of qubits, and fault tolerant error correction do not exist. The Noisy Intermediate Scale Quantum devices exhibit disputable quantum advantage in some academic problems. In this situation, analogue and digital quantum simulators offer the most immediate access to study open problems in physics and chemistry. I will review recent efforts of the ICFO Quantum Theory Group to design, analyse and numerically simulate quantum simulators of interesting 1D and quasi-1D models that exhibit topological order and mimic important phenomena of condensed matter and high energy physics. If time permits, I will also include in this report twistronics without the twist and self-trapped polarons and topological Defects in a topological Mott insulator.

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Joint seminar of Institute of Theoretical Physics and Astronomy

Speaker: Mariusz Gajda (Institute of Physics, Polish Academy of Sciences)
Date and time: Tuesday, April 6 at 14:00 Vilnius time
Location: MSTeams meeting

Title: Quantum droplets – stability, zero-modes and collisions

Ultracold atomic systems are kept in magnetic or dipole trap. The trap prevents atoms from escape. When attractive interactions between two trapped Bose-Einstein condensates are so large that the system is about to collapse, the mixture can form a self-bound droplet. No external potential is needed to keep atoms in space. The system is stabilized by quantum fluctuations – the energy of Bogoliubov vacuum.
In my talk I will discuss the stability of Bose-Bose droplets and formulate stability criterion. Then I will introduce a concept of zero-energy excitations of a two-component droplet. These zero-modes must appear in droplet’s excitation spectrum as a result of 3 broken continuous symmetries. They correspond to translations of a droplet and shifts of phases of its two wavefunctions. Finally, utilizing Hamiltonian of these zero-modes I will address the issue of  coherent collisions of two droplets.

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Joint seminar of Institute of Theoretical Physics and Astronomy

Speaker: Da-Wei Wang (Department of Physics, Zhejiang University)
Date and time: Tuesday, March 30 at 14:00 Vilnius time
Location: MSTeams meeting

Title: Topological phases of quantized light

Abstract: Topological photonics is an emerging research area that focuses on the topological states of classical light. Here we reveal the topological phases that are intrinsic to the particle nature of light, i.e., solely related to the quantized Fock states and the inhomogeneous coupling between them. The Hamiltonian of two cavities coupled with a two-level atom is an intrinsic one-dimensional Su-Schriefer-Heeger model of Fock states. By adding another cavity, the Fock-state lattice is extended to two dimensions with a honeycomb structure, where the strain due to the inhomogeneity of the coupling strengths induces a Lifshitz topological phase transition between a semimetal and three band insulators within the lattice. In the semimetallic phase, the strain is equivalent to a pseudomagnetic field, which results in the quantization of the Landau levels and the valley Hall effect. We further construct a Haldane model where the topological phases can be characterized by the topological markers. This study demonstrates a fundamental distinction between the topological phases of bosons and fermions and provides a novel platform for studying topological physics in dimensions higher than three.

Reference: Han Cai and Da-Wei Wang*, “Topological phases of quantized light”, National Science Review 8, nwaa196 (2021).

About the speaker: Da-Wei Wang is currently Assistant Professor at Zhejiang University. He obtained his PhD degree from the Chinese University of Hong Kong in 2012. Before joining Zhejiang University in 2017, he was Research Associate Professor at Texas A&M University. Prof. Wang's research focuses on the quantum simulation and quantum control in atom-photon interacting systems, such as in superradiance lattices and superconducting circuits. Recently he and his collaborators observed chiral edge currents in room-temperature atoms and synthesized several many-body interactions in superconducting circuits, including DM interaction, chiral spin interaction and three-body spin exchange interaction.

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Joint seminar of Institute of Theoretical Physics and Astronomy

Speaker: Andreas Hemmerich (Hamburg University)
Date and time: Tuesday, March 23 at 14:00 Vilnius time
Location: MSTeams meeting

Title: Dissipative time crystal in an atom-cavity system

I will review our recent research on time crystal dynamics in an atom-cavity system. In contrast to discrete time crystals in driven closed systems, where dissipation constitutes an undesired obstacle, I will discuss an ansatz, where tailored dissipation, induced via controlled coupling to a suitable environment, stabilizes time crystal dynamics. The central signature in our implementation is a period doubled switching between distinct chequerboard density wave patterns, arising through spontaneous symmetry breaking, induced by the interplay between controlled cavity-dissipation, cavity-mediated interactions and external driving. We demonstrate remarkable robustness of this dynamical phase against system parameter changes and temporal perturbations of the driving.

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Joint seminar of Institute of Theoretical Physics and Astronomy

Speaker: Patrik Öhberg (Heriot - Watt University, United Kingdom)
Date and time: Wednesday, March 3 at 14:00 Vilnius time
Location: MS Teams Meeting

Title: The photonic lattice as a general physics emulator

In this talk we will discuss photonic lattices and how they can be used to emulate a number of physical phenomena. A photonic lattice is an array of wave guides where the light in each wave guide is coupled to the neighbouring wave guide. The transversal dynamics can be described as a discrete 2D system which is governed by a Schrödinger equation. In this talk we will show how to emulate various different Hamiltonians and discuss how synthetic nonlinearities can be created in these often inherently linear systems.

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Joint seminar of Institute of Theoretical Physics and Astronomy

Speaker: Kzystof Sacha (Krakow University, Poland)
Date and time: Friday, February 5 at 14:00 Vilnius time
Location: MS Teams meeting

Title: Time Crystals and Time Engineering

Time crystals are characterized by regularity that single-particle or many-body systems manifest in the time domain, closely resembling the spatial regularity of ordinary space crystals. Crystalline structure in time can form spontaneously when a many-body system breaks time translation symmetry of the Hamiltonian but it can also be engineered by suitable external time-periodic driving of a system. Time engineering not only allows one to reproduce condensed matter phases in the time domain but also gives the opportunity to create novel objects that have not been realized so far. As an example, the concept of Anderson molecules will be described which form not due to attractive interactions between atoms but thanks to destructive interference phenomena.

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Joint seminar of Institute of Theoretical Physics and Astronomy

Speaker: Emilia Witkowska (Institute of Physics, Polish Academy of Sciences, Warsaw)
Date and time: Wednesday, January 20 at 14:00 - 15:00 (Vilnius time)
Location: MS Teams meeting

Title: Producing and storing spin-squeezed states and Greenberger-Horne-Zeilinger states in a one-dimensional optical lattice

During the seminar, I will talk about our latest work [1] concerning dynamical generation and storage of spin squeezed states, as well as more entangled states up to macroscopic superpositions, in a system composed of a few ultra-cold atoms trapped in a one-dimensional optical lattice. The system, initially in the superfluid phase with each atom in a superposition of two internal states, is first dynamically entangled by atom-atom interactions then adiabatically brought to the Mott-insulator phase with one atom per site where the quantum correlations are stored. Exact numerical diagonalization allows us to explore the structure of the stored states by looking at various correlation functions, on-site and between different sites, both at zero temperature and at finite temperature, as it could be done in an experiment with a quantum-gas microscope.

[1] M. Płodzień, M. Kościelski, E. Witkowska, A. Sinatra, Phys. Rev. A 102, 013328 (2020)

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Joint seminar of Institute of Theoretical Physics and Astronomy

 

Title: Probing Floquet topological invariants with ultracold atoms

The classification of topological Floquet systems with time-periodic Hamiltonians transcends that of static systems. For example, spinless fermions in periodically driven two-dimensional lattices are not completely characterized by the Chern numbers of the quasienergy bands, but rather by a set of winding numbers associated with the quasienergy gaps [Rudner et al. PRX 3, 031005 (2013)]. I will present two schemes for probing these winding numbers in experiments with ultracold atoms in driven optical lattices. The first one relies on the tomography of band-touching singularities occurring when adiabatically connecting the driven system to a trivial high-frequency regime [1,2] . The second one is based on observing the far-from-equilibrium micromotion of the driven system over two driving periods after a sudden quench into the target Hamiltonian [3]. It relies on the identification of the winding numbers with an Hopf invariant characterizing the micromotion operator.

[1] How to Directly Measure Floquet Topological Invariants in Optical Lattices, FN Ünal, B Seradjeh, A Eckardt, Phys. Rev. Lett. 122, 253601 (2019).
[2] Realization of an anomalous Floquet topological system with ultracold atoms, K Wintersperger, C Braun, FN Ünal, A Eckardt, M Di Liberto, N Goldman, I Bloch, M Aidelsburger, Nat. Phys. 16, 1058 (2020).
[3] Hopf characterization of two-dimensional Floquet topological insulators, FN Ünal, A Eckardt, RJ Slager, Phys. Rev. Research 1, 022003(R) (2019).

Mokslinės konferencijos

14th European Conference on Atoms Molecules and Photons
2022 06 27 - 07 01  Vilnius, Lietuva

Daugiau informacijos puslapyje https://www.ecamp14.org/.

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Įvykusios konferencijos

Konferencija "Controlling quantum matter: From ultracold atoms to solids"

Liepos 29 - Rugpjūčio 2, 2018, Vilnius, Lietuva

Daugiau informacijos puslapyje http://www.hk18.ff.vu.lt/.

 

 

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Astrobiologijos konferencija "From star and planet formation to early Life"

Balandžio 25 - 28 2016, Vilnius, Lietuva

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Gaia-ESO Survey 2015 konferencija

Gruodžio 1-4, 2015, Vilnius, Lietuva

Daugiau informacijos puslapyje http://www.astrospectroscopy.tfai.vu.lt/ges2015/

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Tarptautinė konferencija "Struktūriniai pokyčiai skatinant lyčių lygybę mokslinio tyrimo organizacijose"

2013 m. lapkričio 21-22 d., Vilnius, Lietuva

Daugiau informacijos puslapyje http://www.sapgeric.eu2013.vu.lt/

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Tarptautinė konferencija “Mokslas, inovacijos ir lytiškumas”

Konferencija skiriama antrosios Marija Sklodovska-Kiuri (Marie Skłodowska Curie) Nobelio premijos šimtmečiui paminėti

2011.11.24—25, Vilnius, Lietuva

Daugiau informacijos puslapyje http://www.tfai.vu.lt/curie/

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Lietuvoje įvyks pirmoji tarptautinė kosmoso konferencija

Spalio 6–8 d., 2010 m., Lietuva

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Tarptautinė konferencija ICAMDATA 2010

Rugsėjo 21-24 d., 2010m., Vilnius, Lietuva

Daugiau informacijos puslapyje http://www.itpa.lt/icamdata2010/

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Pirmasis BalticGrid projekto susitikimas

Balandžio mėn. 26-28 d., 2006m., Vilnius, Lietuva

2006 metais balandžio mėn. 26-28 dienomis Vilniuje vyks pirmasis BalticGrid projekto visuotinis susitikimas. Dalyvauja projekto partneriai ir svečiai iš 8 šalių. Renginį organizuoja VU Teorinės fizikos ir astronomijos institutas.

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Rizikos fizika

Gegužės 13-16 d., 2006m., Vilnius, Lietuva

2006 m. gegužės 13-16 dienomis Vilniuje, “Europa City” viešbutyje vyks Europos mokslo fondo COST (http://www.cost.esf.org/) P10 programos 'Rizikos fizika' (27 šalys) (http://gisc.uc3m.es/COST-P10/) konferencija ir SUDĖTINGŲ SISTEMŲ MOKSLO seminaras-konferencija, “Workshop on Complex System Science Action”; http://complexsystems.lri.fr/Portal/tiki-index.php.

Lietuvos mokslininkams - tai puiki galimybė išplėsti savo ryšius regione ir visoje Europoje.

Informacija apie jungtinį renginį yra http://physrisk.itpa.lt/, el. paštas .

Vasaros mokyklos ir kursai

Įvykę renginiai

JWST Master Class Workshop

JWST Master Class local workshop in Lithuania for Baltic states will be organized on February 20-21, 2020 in Vilnius, Vilnius University.

Read more.

James Webb Space Telescope is going to be launched soon. The JWST proposal planning tools (APT and ETC) are quite complex. Therefore JWST Master Class will organize a 2-day workshop in Vilnius, Lithuania in order to train participants on how to use these proposal tools and to stimulate proposal ideas. The release date of the JWST Cycle 1 GO (General Observers) Call for Proposals is January 23, 2020 and the deadline for APT (Astronomers Proposal Tool) proposal submission is May 1, 2020.

It is a 2 day workshop where JWST experts will train selected researchers from ESA member states on JWST proposal planning tools, resources and documentation. We plan to have ~20 participants and encourage participation from postdocs and advanced graduate students. Topics of the workshop: JWST mission status and instruments: NIRCam, NIRSpec, NIRISS, MIRI, available proposal tools and end-to-end tools usage, available observing science modes and observing strategies.

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EUROPLANET Summer School 2019

Space missions: ground-based observations and science communication

Birželio 11-21 d., 2019 m., Molėtų astronomijos observatorija, Lietuva

Daugiau informacijos puslapyje.

Europlanet 2020 (RI) and the Molėtai Astronomical Observatory (ITPA VU) are pleased to announce the international research summer school „Space missions: ground-based observations and science communication“. The aim of the course is to give participants a thorough, multidisciplinary introduction into space missions and the ground-based observations required by space missions before and after launch, as well as an introduction to science communication. More general subjects about specific space missions (TESS, JWST, PLATO…), planetary systems, habitability of planets, photometric and spectroscopic techniques will be presented. Participants will be given some hands-on experience with analysis of stellar chemical composition, detection of stellar variability and/or exoplanets using the Molėtai Astronomical Observatory telescopes (CCD photometry and high-resolution spectroscopy). In addition, the course will give participants the opportunity to develop comprehensive theoretical and practical skills in science communication and engaging with a range of lay audiences, including the public, media, policy makers, schools and educators. The course is open to PhD and master students, early career scientists, and amateur astronomers.

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EUROPLANET Summer School 2018

Europlanet 2018 Aukštieji astrofizikos kursai Molėtų observatorijoje

Kosminės misijos: antžeminiai stebėjimai ir mokslinė komunikacija

Liepos 31 - Rugpjūčio 10 d., 2018, Molėtų astronomijos observatorija, Lietuva

Daugiau informacijos puslapyje.

Europlanet 2020 (RI) and the Molėtai Astronomical Observatory (ITPA VU) are pleased to announce the international research summer school „Space missions: ground-based observations and science communication“. The aim of the course is to give participants a thorough, multidisciplinary introduction into space missions and the ground-based observations required by space missions before and after launch, as well as an introduction to science communication. More general subjects about specific space missions (TESS, JWST, PLATO…), planetary systems, habitability of planets, photometric and spectroscopic techniques will be presented. Participants will be given some hands-on experience with analysis of stellar chemical composition, detection of stellar variability and/or exoplanets using the Molėtai Astronomical Observatory telescopes (CCD photometry and high-resolution spectroscopy). In addition, the course will give participants the opportunity to develop comprehensive theoretical and practical skills in science communication and engaging with a range of lay audiences, including the public, media, policy makers, schools and educators. The course is open to PhD and master students, early career scientists, and amateur astronomers.

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EUROPLANET Summer School 2017

Space missions: ground-based observations and science communication

Liepos 18-28 d., 2017 m., Molėtų astronomijos observatorija, Lietuva

Daugiau informacijos puslapyje.

Europlanet 2020 (RI) and the Molėtai Astronomical Observatory (ITPA VU) are pleased to announce the international research summer school „Space missions: ground-based observations and science communication“. The aim of the course is to give participants a thorough, multidisciplinary introduction into space missions and the ground-based observations required by space missions before and after launch, as well as an introduction to science communication. More general subjects about specific space missions (Gaia, PLATO, TESS...), planetary systems, habitability of planets, photometric and spectroscopic techniques will be presented. Participants will be given some hands-on experience with analysis of stellar chemical composition, detection of stellar variability and/or exoplanets using the Molėtai Astronomical Observatory telescopes (CCD photometry and high-resolution spectroscopy). In addition, the course will give participants the opportunity to develop comprehensive theoretical and practical skills in science communication and engaging with a range of lay audiences, including the public, media, policy makers, schools and educators. The course is open to PhD and master students, early career scientists, and amateur astronomers.

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Projekto „Nacionalinės mokslo populiarinimo sistemos plėtra ir įgyvendinimas“ moksleivių stovykla

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Exoplanets 2016 Aukštieji astrofizikos kursai Molėtų observatorijoje

Rugpjūčio 2-12 d., 2016 m., Molėtų astronomijos observatorija, Lietuva

Daugiau informacijos puslapyje.

The aim of the course is to give participants a thorough multidisciplinary introduction into the field of exoplanets, their detection, types, characterization, and the possibility of life on exoplanets. In addition, more general planetary subjects like formation of planetary systems, habitability of planets, and physical processes in planetary atmospheres will be covered. To give participants some hands-on experience with detection of exoplanets, observations of several exoplanet transits using the Molėtai Astronomical Observatory telescopes will be carried out. The course is open to PhD and master students, early career scientists, and amateur astronomers.

 

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LifeOrigins 2015 Aukštieji astrofizikos kursai Molėtų observatorijoje

"Formation and evolution of planetary systems and habitable planets"

Rugpjūčio 21 - 30 d., 2015 m., Molėtai, Lietuva

Daugiau informacijos puslapyje http://www.nordicastrobiology.net/Moletai2015/.

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NordForsk school 2012

Aukštieji astrofizikos kursai molėtų observatorijoje

Liepos 28 - Rugpjūčio 11 d., 2012, Molėtų astronomijos observatorija, Lietuva

The course will be aimed at students in the first years of their PhD studies, and contain lectures by internationally top scientists, observations, exercises and assignments based mostly on own observations. The participants, who will end the Course with a successful presentation of work on the large assignment will be recommended to 6 ECU credits towards a doctoral degree. 4 ECU study credits can be earned additionally by describing original results in a form of scientific paper.

Daugiau informacijos puslapyje.

 

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Europos astrofizikai tobulinasi Molėtų observatorijoje

Liepos 14-27 d., 2011 m., Molėtų astronomijos observatorija, Lietuva

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NEON summer school 2011

Liepos 14-27 d., 2011 m., Molėtų astronomijos observatorija, Lietuva

Daugiau informacijos puslapiuose:
http://mao.tfai.vu.lt/schools/index.php?option=com_content&task=view&id=57&Itemid=77
http://www.iap.fr/opticon/neon_schools/2011/
http://www.iap.fr/opticon/past_neon_schools/2011/index.html

The purpose of the summer schools is to provide the opportunity for young researchers to gain practical experience in observational techniques, data reduction and analysis and the use of virtual observatory tools. Students will carry out small research projects, centered on selected astrophysical topics, in small groups under the supervision of experienced astronomers. These practical exercises will be complemented by lectures on general observational techniques and archival research for both ground and space based astronomy.

The principles are the same as in previous schools: introductory lectures on topics of general interest, work in small groups, execution of a real research project, presentation of the results at the end of the school.

Observations will be made with: - The Moletai 1.65m telescope for photometry
-The Nordic Optical Telescope (2.5m) in remote control for spectroscopy

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BalticGrid-II vasaros mokykla

Birželio birželio 29 – liepos 03, 2009

The main objectives of the BalticGrid-II Summer School were to educate the end users in the field of the Grid computing in the Baltic region and Belarus. The school brought together scientists from Poland, Lithuania, Latvia, Estonia, Belarus and spread information about Grid possibilities and opportunities in the region.

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NordForsk school 2008

Rugpjūčio 10-24 d., 2008 m., Molėtų astronomijos observatorija, Lietuva

The aim of the course is to give participants a modern knowledge of how to observe and interpret stellar spectra and pulsations, by doing own observations, interpret existing observations and do theoretical modelling. The main topics of the course is to teach methods for investigation of stellar main atmospheric parameters, the detailed chemical composition, influence of the magnetic fields, mixing and diffusion of material in stellar atmospheres, asteroseismology, investigation of surface structures, and search for exoplanets. The highest priority will be given to observational techniques and doing of own observations. Both photometric and spectroscopic observing techniques will be taught and tried out at telescopes.

Five telescopes with modern detectors will be available for observations, three at the Moletai Observatory in Lithuania, and two at Canary Islands remotely operated - the Nordic Optical Telescope at La Palma and IAC80 Teide Observatory telescope at Teide.

Plačiau apie mokyklą.

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Paskaitų ciklas "Europos Jungtinis tyrimų centras: mokslas – pramonė - produktas - vartotojas – mokslas"

Vasario 25-29, 2008 m.

Plačiau apie renginį.

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Paskaitų ciklas "Sinchrotroninė spinduliuotė – instrumentas ateičiai keisti"

Lapkričio 05-09 d., 2007

Plačiau apie renginį.

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Vasaros kvalifikacinė mokykla VU TFAI Molėtų AO "Virtualios observatorijos"

Spalio 15-26 d., 2007 m.

Plačiau apie renginį.

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Vasaros kvalifikacinė mokykla VU TFAI Molėtų AO "Astronominių duomenų analizės programinė įranga"

Gegužės 21-25 d., 2007 m.

Plačiau apie renginį.

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Paskaitų ciklas "Tarptautinis termobranduolinis eksperimentinis reaktorius ITER - energetikos perspektyva"

Kovo 26-30 d., 2007 m.

Plačiau apie renginį.

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Kvalifikacinė mokykla Kursai "ESO duomenų bazės ir jų panaudojimas"

Spalio 9-13 d., 2006 m., Molėtų astronomijos observatorija, Lietuva

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Paskaitų ciklas "Europos branduolinių tyrimų centras CERN atskleidžia medžiagos sandaros paslaptis"

Lapkričio 06-10 d., 2006

Plačiau apie paskaitų ciklą.

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NordForsk school 2005

Šiaurės ir Baltijos šalių aukštieji astrofizikos kursai VU TFAI Molėtų astronomijos observatorijoje

Rugpjūčio 7-21 d., 2005, Molėtų astronomijos observatorija, Lietuva

Plačiau apie mokyklą.

 

 

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NordForsk school 2002

Šiaurės ir Baltijos šalių aukštieji astrofizikos kursai VU TFAI Molėtų astronomijos observatorijoje

Rugpjūčio 11 - 25 d., 2002 m., Molėtų astronomijos observatorija, Lietuva

Plačiau apie mokyklą.

 

 

 

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NordForsk school 1999

Šiaurės ir Baltijos šalių aukštieji astrofizikos kursai VU TFAI Molėtų astronomijos observatorijoje

Rugpjūčio 29 - rugsėjo 12, 1999 m., Molėtų astronomijos observatorija, Lietuva

Plačiau apie mokyklą.

Kiti renginiai

Įvykę renginiai

Jono Bialopetravičiaus daktaro disertacijos gynimas

Gruodžio 18 d., 2020 m., 11 val. JONAS BIALOPETRAVIČIUS gins disertaciją „Žvaigždžių spiečių analizė konvoliuciniais neuroniniais tinklais ” fizikos mokslo krypties daktaro laipsniui gauti.

Stebėti disertacijos gynimą galite nuotoliniu būdu pasinaudodami nuoroda.

Disertacija rengta 2015 – 2020 metais Vilniaus universitete.

Disertaciją galima peržiūrėti:
Vilniaus universiteto, Fizinių ir technologijos mokslų centro bibliotekose ir svetainėje adresu:https://www.vu.lt/naujienos/ivykiu-kalendorius/20201218
https://is.vu.lt/pls/pub/ivykiai.ivykiai_prd?p_name=FA7D21E61B861AD07A87C3A8580E9633/BIALOPETROVICIUS%20Jonas.pdf

arba VU FF TFAI puslapyje.

Mokslinius tyrimus rėmė Lietuvos mokslo taryba.

 

Mokslinis vadovas – dr. Donatas Narbutis (Vilniaus universitetas, gamtos mokslai, fizika – N 002).

Disertacijos gynimo tarybos sudėtis:
dr. Arūnas Kučinskas – tarybos pirmininkas (Vilniaus universitetas, gamtos mokslai, fizika – N 002),
dr. Mindaugas Karčiauskas (Madrido Komplutensės universitetas , Ispanija, gamtos mokslai, fizika – N 002),
dr. Šarūnas Mikolaitis (Vilniaus universitetas, gamtos mokslai, fizika – N 002),
dr. Julius Sperauskas (Vilniaus universitetas, gamtos mokslai, fizika – N 002),
dr. Kastytis Zubovas (Fizinių ir technologijos mokslų centras, gamtos mokslai, fizika – N 002).

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Adolfo Jucio kasmetiniai akademiniai skaitymai

2018 m. rugsėjo 12 d. (trečiadienį) 15 val. kviečiame į

Adolfo Jucio kasmetinius
akademinius skaitymus, skirtus žymaus Lietuvos fiziko, mokslo organizatoriaus, pedagogo, akademiko Adolfo Jucio (1904–1974) gimtadieniui.
Renginys vyks Nacionaliniame fizinių ir technologijos mokslų centre, Saulėtekio al. 3, Vilnius, D401 auditorijoje (IV a.).

PRANEŠIMAI
Prof. BRONISLOVAS KAULAKYS, Spektroskopija: nuo Rydbergo atomų iki 1/f triukšmo.
Dr. JULIUS RUSECKAS, Labai šaltos dujos, lėta šviesa ir Rydbergo atomai.
Pranešimų autoriams, 2017 m. A. Jucio premijos laureatams, Lietuvos mokslų akademijos prezidentas akad. Jūras Banys įteiks A. Jucio medalius.

 

 

 

 

 

 

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"Žvaigždės ir egzoplanetos" Vieša paskaita Molėtų astronomijos observatorijoje

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Nobelio premijos laureato Wolfgang Ketterle vieša paskaita Vilniaus Universitete

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"Kosminės erdvės įkvėpti" tiesioginė transliacija iš Molėtų astronomijos observatorijos

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CERN mokslininkas baigia paskaitų ciklą apie subatominių dalelių registravimo ypatumus

Lapkričio pradžioje Vilniaus universiteto Fizikos fakultete Europos dalelių fizikos organizacijos (CERN) mokslininkas, eksperimentinės fizikos specialistas dr. Christophas Schäferis baigs skaityti paskaitų seriją "Dalelių sąveika su materija ir detektorių kūrimo principai".

Daugiau informacijos: http://naujienos.vu.lt/cern-mokslininkas-baigia-paskaitu-cikla-apie-subatominiu-daleliu-registravimo-ypatumus/

Ketvirtoji, paskutinė paskaita "Particle Interactions with Matter and Detector Design Principles" vyks lapkričio 3 d. 9 val. VU Fizikos fakulteto 815 auditorijoje (Saulėtekio al. 9-III). Paskaita vyks anglų kalba.

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CERN mokslininkas aptars subatominių dalelių registravimo ypatumus

Lapkričio pradžioje Vilniaus universiteto Fizikos fakultete Europos dalelių fizikos organizacijos (CERN) mokslininkas, eksperimentinės fizikos specialistas dr. Christophas Schäferis tęs paskaitų seriją „Dalelių sąveika su materija ir detektorių kūrimo principai“. Tai trečioji iš keturių numatytų paskaitų apie eksperimentinį dalelių detektavimą.

Daugiau informacijos: http://naujienos.vu.lt/cern-mokslininkas-aptars-subatominiu-daleliu-registravimo-ypatumus/

Trečioji paskaita „Particle Interactions with Matter and Detector Design Principles“ vyks lapkričio 2 d. 16 val. VU Fizikos fakulteto 212 auditorijoje (Saulėtekio al. 9-III). Paskaita vyks anglų kalba.

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Tyrėjų naktis - 2016 Molėtų astronomijos observatorijoje

Rugsėjo 30 d. Vilniaus universiteto Teorinės fizikos ir astronomijos instituto Molėtų astronomijos observatorija dvyliktą kartą kviečia į Tyrėjų naktį. “Tyrėjų naktis – 2016”, tai šventė, kurios tikslas – arčiau supažindinti visuomenę su greta jų dirbančiais mokslininkais, suprantamai ir patraukliai paaiškinti jų atliekamų tyrinėjimų ir ieškojimų esmę ir naudą visuomenei, parodyti, kad ir mokslininkai randa laiko pramogoms ir poilsiui.

Šį vakarą daugelio Europos šalių gyventojai šimtuose miestų lankysis mokslinėse laboratorijose ir observatorijose, klausys mokslininkų paskaitų, stebės mokslinius eksperimentus, diskutuos su tyrėjais. Jei leis oro sąlygos, pro mėgėjiškus teleskopus bus galima pasigėrėti nakties dangaus grožybėmis.

Paskaitų programa

Didžioji salė:

19 val. 00 min. J. Sūdžius „Šiuolaikiniai teleskopai“
19 val. 30 min. J. Tamulienė „Gydomoji deimantų galia“
20 val. 00 min. E. Norvaišas „Ar CERN juodoji skylė praris ir mus?“
20 val. 30 min. E. Pakštienė „Egzoplanetų beieškant“
21 val. 00 min. R. Ženovienė „Gyvybės paieškos kitose planetose”
21 val. 30 min. J. Klevas „Kas yra žvaigždė?”
22 val. 00 min. A. Drazdauskas „Kosminės observatorijos“
22 val. 30 min. O. Rancova „Kaip įžiebti žvaigždę Žemėje“

Mažoji salė:

19 val. 00 min. R. Ženovienė „Gyvybės paieškos kitose planetose”
19 val. 30 min. J. Klevas „Kas yra žvaigždė?”
20 val. 00 min. A. Drazdauskas „Kosminės observatorijos“
20 val. 30 min. O. Rancova „Kaip įžiebti žvaigždę Žemėje“
21 val. 00 min. J. Sūdžius „Šiuolaikiniai teleskopai“
21 val. 30 min. J. Tamulienė „Gydomoji deimantų galia“
22 val. 00 min. E. Norvaišas „Ar CERN juodoji skylė praris ir mus?“
22 val. 30 min. E. Pakštienė „Egzoplanetų beieškant“

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Kelionė į egzoplanetas, Molėtų astronomijos observatorijoje Šeštadienis, rugpjūčio 6 d. 12:30

Šeštadienis, rugpjūčio 6 d. 12:30
Viešas renginys paskaitos Molėtų astronomijos observatorijoje

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Viešas renginys: Kometos – Naujausios žinios iš Rosetta zondo

Comets – New insights from Rosetta

Public event at the Vilnius Planetarium, Konstitucijos ave. 12a
Sunday, 24 April 2016, 17:00

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Aleksejaus Kononovičiaus daktaro disertacijos gynimas

Gruodžio 18 d. (penktadienį) 14 val. VU Konfucijaus instituto salėje (A. Goštauto 12, 432 kab., Vilnius) Aleksejus Kononovičius gins disertaciją „Finansų rinkų ir socialinių procesų modeliavimas statistinės fizikos metodais“ fizinių mokslų srities, fizikos mokslo krypties daktaro laipsniui gauti.

Disertacija rengta 2011–2015 m. Vilniaus universiteto Teorinės fizikos ir astronomijos institute. Mokslinis vadovas – dr. Vygintas Gontis (Vilniaus universitetas, fiziniai mokslai, fizika – 02P).

Disertacija bus ginama fizikos mokslo krypties taryboje:
habil. dr. Evaldas Tornau – tarybos pirmininkas (Fizinių ir technologijos mokslų centras, fiziniai mokslai, fizika – 02P),
prof. dr. Egidijus Anisimovas (Vilniaus universitetas, fiziniai mokslai, fizika – 02P),
prof. habil. dr. Remigijus Leipus (Vilniaus universitetas, fiziniai mokslai, matematika – 01P),
prof. habil. dr. Kęstutis Pyragas (Fizinių ir technologijos mokslų centras, fiziniai mokslai, fizika – 02P),
prof. habil. dr. Kęstutis Staliūnas (Katalonijos politechnikos universitetas, Ispanija, fiziniai mokslai, fizika – 02P).

Disertaciją galima peržiūrėti Vilniaus universiteto, Fizinių ir technologijos mokslų centro bibliotekose.

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Renatos Ženovienės daktaro disertacijos gynimas

Š. m. gegužės 6 dieną (trečiadienį) 14 val. ketvirto aukšto salėje vyks

RENATOS ŽENOVIENĖS

disertacijos gynimas. Disertacijos tema:

CHEMINĖS SUDĖTIES TYRIMAS GALAKTIKOS ŽVAIGŽDŽIŲ SUBSTRUKTŪROSE
(angl.: CHEMICAL COMPOSITION STUDY OF GALACTIC STELLAR SUBSTRUCTURES)

Vadovė: habil. dr. Gražina Tautvaišienė

Maloniai kviečiame dalyvauti!

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Žvaigždėtosios naktys 2015

Data: balandžio 24 d., penktadienis, pradžia 19.00 val.
Vieta: Molėtų astronomijos observatorija, Kulionys, Molėtų rajonas.

Numatoma programa (eiliškumas gali keistis):

Dr. Algirdas Kazlauskas, VU TFAI. - Edvinas Hablas – žmogus ir astronomas
Macijauskas Mindaugas, VU TFAI. - 25 Hablo kosminio teleskopo metai.
Povilas Narbutas, astronomijos mėgėjas, Vilnius. - “Tekančios Saulės šalies kosminės ambicijos”
2015 m. kovo 20 dienos Saulės užtemimas Lietuvoje – įspūdžiai iš Vilniaus, Kauno, Kėdainių, Klaipėdos.
Andrius Zigmantas, astronomijos mėgėjas, Vilnius. - “Kaip man (nesi)sekė(si) dangų fotografuoti”
Povilas Narbutas, astronomijos mėgėjas, Vilnius. - Internetinio portalo “Zondas” pristatymas.

Vyks vakarinis filmų seansas – keliausime tarp žvaigždžių erdve ir laiku.

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Tyrėjų naktis Molėtų astronomijos observatorijoje

Rugsėjo 26 d. kviečiame į jubiliejinę, dešimtąją Tyrėjų naktį Vilniaus universiteto Teorinės fizikos ir astronomijos instituto Molėtų astronomijos observatorijoje.

“Tyrėjų naktis – 2014”, tai šventė, kurios tikslas – arčiau supažindinti visuomenę su greta jų dirbančiais mokslininkais, suprantamai ir patraukliai paaiškinti jų atliekamų tyrinėjimų ir ieškojimų esmę ir naudą visuomenei, parodyti, kad ir mokslininkai randa laiko pramogoms ir poilsiui. Šį vakarą daugiau nei 30 Europos šalių gyventojų trijuose šimtuose miestų lankysis mokslinėse laboratorijose ir observatorijose, stebės mokslinius eksperimentus arba patys bandys juos atlikti, diskutuos su mokslininkais.

Daugiau informacijos - Molėtų observatorijos svetainėje.

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ASTRONET renginys "Forum on Astronomy in Lithuania"

Kviečiame į ASTRONET organizuojamą renginį "Forum on Astronomy in Lithuania", kuris įvyks šių metų rugsėjo 18 d. 9 - 13 val. VU TFAI Planetariume.

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Šarūno Masio Daktaro disertacijos gynimas

2014-06-19

Vilniaus universiteto Teorinės fizikos ir astronomijos institute A. Goštauto g. 12, Vilnius, 432 k. (salėje) 2014 m. birželio 19 d. (ketvirtadienį), 14:00 val. vyks Šarūno Masio daktaro disertacijos gynimas.

Disertacijos tema: "Perovskitinių kristalų elektroninės ir kristalinės sandaros tyrimas".

Kviečiame dalyvauti!

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Tarptautinė konferencija "Struktūriniai pokyčiai skatinant lyčių lygybę mokslinio tyrimo organizacijose"

(SAPGERIC, 2013 m. lapkričio 21-22 d., http://www.sapgeric.eu2013.vu.lt/)

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2013-09-01 iki 05 TLL-COLIMA-FOTONIKA seminaras

Daugiau informacijos: http://www.itpa.lt/Vilnius_2013_LT_LV_TW/

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Žvaigždėtos Naktys 2013

2013 m. gegužės 17 d. Molėtų astronomijos observatorijoje vyks Žvaigždėtųjų Naktų renginiai

Paskaitos:
19.00 - 19.50 "Taikonautika - Kinijos pilotuojamoji kosmonautika" Valentinas Šaltenis, Anykščiai
20.00 - 20.50 "Lietuvių indėlis kosminių technologijų plėtrai pasaulyje" Saulius Lapienis - Kosmoso mokslo ir technologijų instituto direktorius plėtrai ir Lietuvos inovacijų centro projektu konsultantas, Vilnius
21.00 - 21.20 "Kosmosas mene" Monika Vosyliūtė, Ernest Pauliučenko, Vilnius
21.25 - 21.55 "LituanicaSAT-1 - pirmasis palydovas šalies istorijoje". Laurynas Mačiulis (misijos technikos vadovas), Vytenis Buzas (misijos vadovas)
22.00 - ... Astronominis protmušis. Komandos į protmušį registruojasi bendroje renginio registracijoje
22.00 - Albireo klubo teleskopai Astronomijos observatorijos kieme - naktinio dangaus stebėjimai

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Tyrėjų naktis Molėtų astronomijos observatorijoje

Kviečiame į mokslo šventę “Tyrėjų naktis – 2011” Vilniaus universiteto Teorinės fizikos ir astronomijos instituto Molėtų astronomijos observatorijoje.

“Tyrėjų naktis – 2011”, tai šventė, kurios tikslas – arčiau supažindinti visuomenę su greta jų dirbančiais mokslininkais, suprantamai ir patraukliai paaiškinti jų atliekamų tyrinėjimų ir ieškojimų esmę ir naudą visuomenei, parodyti, kad ir mokslininkai randa laiko pramogoms ir poilsiui. Šį vakarą daugelio Europos šalių gyventojai lankysis mokslinėse laboratorijose ir observatorijose, stebės mokslinius eksperimentus arba patys bandys juos atlikti, diskutuos su mokslininkais.

Daugiau informacijos - Molėtų observatorijos svetainėje.

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Eduardo Puzero daktaro disertacijos gynimas

Šių metų rugsėjo 20 dieną (antradienį) 14 val. TFAI (Goštauto 12)
salėje (4 aukšte) bus ginama Eduardo Puzero daktaro disertacija
"Evolutionary effects in helium core burning star atmospheres".

Disertacijos ir santraukos tekstai puslapyje.

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Adolfo Jucio akademiniai skaitymai, Rugsėjo 13 d. 14 val.

Maloniai kviečiame 2011 m. rugsėjo 13 d. (antradienį) 14 val. į Adolfo Jucio akademinius skaitymus

Tai kasmetiniai skaitymai, skirti žymaus Lietuvos fiziko, mokslo organizatoriaus, pedagogo, akademiko Adolfo Jucio (1904–1974) gimtadieniui.

Renginys vyks VU Teorinės fizikos ir astronomijos institute (A. Goštauto g. 12, IV a., aktų salėje).

Pranešimai
1. Habil. dr. Evaldas Tornau, prof. Romualdas Karazija.
Lietuvos fizikos žurnalo penkiasdešimtmetis: raida ir dabartinės
problemos.
2. Prof. Algirdas Matulis. Kvantinis žiedelis ir negęstanti srovė jame.

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Aviacinės fotografijos konkurso paroda Molėtų astronomijos observatorijoje

Paroda Molėtų astronomijos observatorijoje veiks iki metų pabaigos

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Algebrinis daugiadalelės trikdžių teorijos plėtojimas teorinėje atomo spektroskopijoje - disertacijos gynimas 2010 12 21, 15:00

SKELBIMAS
2010 m. gruodžio mėn. 21 d. 15 val. Vilniaus universiteto Teorinės fizikos ir astronomijos instituto bibliotekoje (III a., A. Goštauto g. 12, LT-01108, Vilnius)
Rytis Juršėnas gins disertaciją
Algebrinis daugiadalelės trikdžių teorijos plėtojimas teorinėje atomo spektroskopijoje
fizinių m. sr. fizikos kr. daktaro laipsniui gauti.

Vilniaus universiteto
Fizikos mokslo krypties tarybos sudėtis:
PIRMININKAS:
Prof. habil. dr. Zenonas RUDZIKAS (VU, fiziniai mokslai, fizika – 02P)
NARIAI:
1. Prof. habil. dr. Feliksas IVANAUSKAS (VU, fiziniai mokslai, matematika – 01P)
2. Prof. habil. dr. Gintautas KAMUNTAVIČIUS (VDU, fiziniai mokslai, fizika – 02P)
3. Prof. dr. Paulius MIŠKINIS (VGTU, fiziniai mokslai, fizika – 02P)
4. Prof. dr. Egidijus NORVAIŠAS (VU, fiziniai mokslai, fizika – 02 P)
OPONENTAI:
1. Prof. habil. dr. Gediminas GAIGALAS (VPU, fiziniai mokslai, fizika – 02P)
2. Doc. dr. Valdas ŠPAKAUSKAS (VGTU, fiziniai mokslai, fizika – 02P)
Disertaciją galima peržiūrėti Vilniaus universiteto ir VU Teorinės fizikos ir astronomijos instituto bibliotekose.

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LJMS vasara 2005

Vasaros mokykla moksleiviams "LJMS vasara 2004. Mokslas ir technologijos". vyks 2005 metų liepos 8 - 17 d. Molėtų astronominėje observatorijoje.

Mokyklos metu vyks paskaitos apie pasaulyje vykdomus mokslinius tyrimus, šiuolaikines įvairių mokslo sričių vystymosi tendencijas bei Lietuvos padėtį šiame kontekste. Paskaitas skaitys pasaulyje pripažinti Lietuvos mokslininkai. Be minėtų paskaitų vyks praktiniai užsiėmimai, kurių metu moksleiviai įgys (arba patobulins) mokslinio darbo įgūdžius (eksperimento planavimas, vykdymas, rezultatų apdorojimas; matematinis modeliavimas). Viena diena bus paskirta išvažiuojamajai ekskursijai į aukštųjų technologijų įmones ir laboratorijas.

Mokykla organizuoja Lietuvos jaunųjų mokslininkų sąjunga. Vienas pagrindinių organizatorių sąjungos pirmininkas Tomas Žalandauskas.

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LJMS vasara 2004

Vasaros mokykla moksleiviams "LJMS vasara 2004. Mokslas ir technologijos".

Mokykla organizavo Lietuvos jaunųjų mokslininkų sąjunga. Vienas pagrindinių organizatorių sąjungos pirmininkas Tomas Žalandauskas. Mokykloje dalyvavo Julius Ruseckas.