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The 67th Open Readings 2024 International Conference of Physics and Natural Sciences for students will take place from the 23rd to the 26th of April. 

The conference will welcome more than 350 participants various countries worldwide. Young researchers will present their conducted studies in their selected field from the nine proposed areas of natural sciences and technology. Conference participants and audience members will also have the opportunity to listen to seven invited speakers - world-renowned scientists. Invited speakers such as Prof. Dr. Jens Biegert from the Institute of Photonic Sciences in Spain and Prof. Dr. Ursula Keller from ETH Zurich, Switzerland, will share their expertise in the field of laser physics, while Prof. Dr. Chris Parkes, professor at the University of Manchester in the UK, will introduce the field of particle physics to the participants of the conference. Invited speakers from universities in the United States and Germany will also share their expertise in the fields of chemistry, astronomy and astrophysics, and genetics. 

During the conference, the participants will have the opportunity to listen to a presentation by Dr Makeda Tekle-Smith, a junior professor of chemistry at Columbia University in the United States. Dr Tekle-Smith and her research group focus on exploring the fundamental principles of physical organic chemistry in the field of asymmetric synthesis. Their goal is to develop enantiopure materials, exploit the reactivity of unconventional chiral motifs, and advance the basic understanding of chiral structural effects. The results of the research are aimed to be applied in areas such as pharmaceutical development, biomaterial design and the development of sustainable synthesis methods.

The invited conference speaker, Dr. Andrew Pun, is an Associate Professor of Chemistry and Biochemistry at the University of California, San Diego. Dr. Andrew Pun and his interdisciplinary research group focus on the use of synthetic chemistry to manipulate and study the dynamics of photogenerated excitons. They aim to investigate hybrid semiconductor systems combining the best properties of organic and inorganic semiconductors for applications ranging from catalysis to photovoltaics. During his conference presentation, Dr Andrew Pun will deliver a talk on new applications of up-conversion in the exploration of novel annihilators in chemical synthesis.

During the conference, participants will have the opportunity to hear from the award-winning Prof. Dr. Charles Elachi, who was the eighth Director of the Jet Propulsion Laboratory and Vice President of Caltech from 2001 to 2016. Dr Elachi is currently a Professor of Electrical Engineering and Planetary Science at the California Institute of Technology. Prof. Elachi's research focuses on the use of space-based active microwave instruments to remotely probe planetary surfaces, including spheres and subsurface surfaces. His specialisation includes the analysis and interpretation of radar images of various planetary surfaces, with a primary focus on the Earth. During his presentation, Prof. Dr Charles Elachi will talk about space exploration and the prospects for the next 25 years in this field.

Participants will also have the opportunity to listen to Dr. Viktorija Glembockytė from the Ludwig and Maximilian University of Munich. Dr Glembockytė's research focuses on process studies and the construction of molecular devices in the nanoscale, using two different but complementary approaches: DNA origami and fluorescence imaging of single molecules. Viktorija is currently actively working on combining these two approaches to create modular and tunable nanosensors. During her conference presentation, Dr Viktorija Glembockytė will talk about nanoscale DNA tools that can be used to create light antennas and thus amplify a molecule's fluorescence signal by several hundred times, allowing the signal to be detected even with a smart phone camera.

The Open Readings 2024 conference will take place between the 23rd and 26th of April at the National Centre for Physical Sciences and Technology. 

Open Readings 2024 is organised by the Faculty of Physics of Vilnius University, the National Centre for Physical Sciences and Technology, SPIE Student Chapter of Vilnius University, Optica Student Chapter of Vilnius University and the European Physical Society Young Minds Section of Vilnius. 

More information about the conference: 

http://www.openreadings.eu/

Today, we come together to honor a significant event - the International Day of Women and Girls in Science. February 11th marks a pivotal moment in our global calendar, a day where we shine a bright light on the remarkable contributions and achievements of women and girls in the field of science.

As we reflect on this day, we are reminded of the countless women and girls who have fearlessly pursued their passion for science, breaking barriers, defying stereotypes, and paving the way for future generations. Their dedication, perseverance, and unwavering commitment have not only enriched the world of science but have also transformed our understanding of the universe and improved the quality of life for countless individuals around the globe.

Today, we honor the trailblazers -  Marie Sklodowska-Curie, Rosalind Franklin, Grace Hopper - who dared to dream beyond societal expectations and blazed a trail for others to follow. Their stories inspire us to push the boundaries of what is possible and to never underestimate the power of our own potential.

But today is not only about celebrating the achievements of the past; it is also about empowering the scientists of the future - our young women and girls who are poised to make their mark on the world. Today, we reaffirm our commitment to providing them with the support, resources, and opportunities they need to thrive in the world of science.

We must encourage and mentor the next generation of female scientists, ensuring that they have the confidence to pursue their passions and the resilience to overcome any obstacles they may face along the way. By nurturing their curiosity, fostering their creativity, and instilling in them a love for discovery, we can unlock their full potential and unleash a wave of innovation that will shape the future of our world.

So, let us use this day as a catalyst for change - a day to inspire, to educate, and to advocate for gender equality in science. Let us celebrate the diversity of voices and perspectives that women and girls bring to the table, recognizing that true progress can only be achieved when we harness the talents of all individuals, regardless of gender.

Together, let us strive to build a world where every woman and girl has the opportunity to pursue her dreams and contribute her unique gifts to the scientific community. Let us work towards a future where gender no longer dictates one's opportunities or success in the world of science.

On this International Day of Women and Girls in Science, young female researchers, doctoral candidates from Vilnius Universityand Kaunas University of Technology, came together and shared what science and their chosen path in doctoral studies mean to them.

On November 25-30, astrophysicists Juan Carlos Suárez Yanes (group leader), Antonio García Hernández, Sebastià Barceló Forteza and Giovanni Mirouh from the Group of Stellar Evolution and Nucleosynthesis at the University of Granada visited Lithuania. The University of Granada (Universidad de Granada) is one of the ten ARQUS European University Alliance members, along with Vilnius University.

The researchers went to the Molėtai Astronomical Observatory (MAO) and the Lithuanian Museum of Ethnocosmology. After returning to Vilnius, they worked on an asteroseismology project at the VU Institute of Theoretical Physics and Astronomy (TFAI), were welcomed by the ambassador of the Kingdom of Spain in Lithuania, María Nieves Blanco Díaz, and visited the historical VU astronomy observatory in the Central building of Vilnius University.

The guests also conducted seminars: Sebastià Barceló Forteza‘s presentation titled ‘The Quest to Analyse Delta Scuti Stars: From Light Curves to Characterised Stars’ and Giovanni Mirouh‘s ‘Asteroseismology of Rapidly-Rotating Stars: Recent Progress on a Challenging Topic’.

The first presentation began with the words of the group leader, Juan Carlos Suárez Yanes, who introduced the team. Meanwhile, the last one was concluded by Antonio García Hernández, who also with the attendees discussed the ongoing and future common projects.

This visit was the continuation of a previous one that Dr Erika Pakštienė and Dr Carlos Viscasillas Vázquez, researchers at the VU TFAI Astrospectroscopy and Exoplanets Group, had at the University of Granada last September. At that time, the primary aim was to model a specific Delta Scuti-type star in a binary system discovered at the Molėtai Astronomical Observatory.

‘Interacting and collaborating with the asteroseismologists from Granada provides us with a chance to enhance our expertise in this valuable and fascinating field of knowledge’, claimed Dr Carlos Viscasillas Vázquez.

‘I am extremely happy that we got in contact with astronomers from Granada University, as we found a lot of mutual interests, which should lead to a scientific production quite soon’, shared Dr Erika Pakštienė.

Congratulations to Dr. Thomas Gajdosik, Lecturer at the Institute of Theoretical Physics and Astronomy, who has been named the best lecturer for 2023.

Dr. Thomas Gajdosik received the most support from the students of the Faculty of Physics in 2023. He is highly respected for his professionalism, academic care, sincerity and attentiveness.

On 15 November, as the world celebrates Philanthropy Day, the family of Dr Algirdas Juozapavičius, a student and colleague of Prof. Algis Petras Piskarskas (1942-2022), has donated EUR 100,000 to the named Prof. Piskarskas Endowment Sub-Fund, established earlier this year at the Vilnius University Foundation, the returns of which will be allocated for the named scholarships to laser physics talents.

The named sub-fund established by Light Conversion, a major ultrafast laser technology company, together with the Piskarskas family, has grown to EUR 300,000 following the Juozapavičius family's contribution, making it the largest endowment sub-fund managed by the VU Foundation.

Dr. Algirdas Juozapavičius is a former shareholder of the company Light Conversion, its long-time CEO (1994-2019), a Doctor of Physical Sciences, one of the pioneers of the Lithuanian laser industry, and has been awarded The Cross of the Knight of the Order for Merits to Lithuania, and the St. Christopher Statue of Vilnius for his contributions to science and business. In 2018, he was elected CEO of the Year by "Verslo žinios".

The 67th International Conference for Students of Physics and Natural Sciences ‘Open Readings 2024’ invites its potential presenters to register!

The annually held ‘Open Readings 2024’ conference gathers over 400 students and researchers worldwide to share their scientific experience. Its participants actively exchange innovative ideas and the results of their latest carried out research. The conference grants the opportunity for BSc, MSc and PhD students to present posters and give talks on their scientific research to a larger audience, receive constructive criticism and insightful advice. The conference as well provides its participants and the general public with a great chance to listen to lectures of leading and accomplished scientists on a wide range of scientific topics. 

The conference also holds a Pupils’ Session, where many of the brightest students in Lithuania partake every year. 

Potential ‘Open Readings 2024’ presenters are invited to register through this link. 

The links for the conference’s main session’s listener registration and the Pupils’ Session’s presenter and listener registration will be published on the main ‘Open Readings’ page. 

The conference will take place on April 23-26, 2024, on-site in the Centre for Physical Sciences and Technology (NFTMC) in Vilnius, Lithuania. In case of any questions arising, please do not hesitate to contact the organisers at . 

In the meantime, we greatly encourage you to actively follow the news on the main ‘Open Readings’  page.

From July 3rd to 5th, nearly 100 quantum physics researchers from around the world will gather in Vilnius. They are attending the international conference Humboldt Kolleg "Synthetic Quantum Matter," organized by the Physics Faculty of Vilnius University in collaboration with the Lithuanian Physical Society. The scientists will share the latest information on synthetic quantum systems, including ultracold atoms, photonic and condensed matter systems.

According to the organizers, the conference theme is closely related to quantum computing, which has recently received significant attention, and the 2022 Nobel Prize in Physics was awarded for outstanding achievements in this field.

"Control of quantum systems is a very important and relevant issue in modern physics due to applications in rapidly advancing fields of quantum informatics, quantum computing, and quantum simulations. In the latter case, the study of well-controlled quantum systems, such as ultracold atoms, helps us better understand the properties of more complex and technologically significant quantum systems and phenomena, such as high-temperature superconductivity," says the main conference organizer, Professor Gediminas Juzeliūnas from the Faculty of Physics at Vilnius University.

The conference will be attended by researchers from Germany, Italy, Austria, Poland, Finland, France, the Netherlands, the United Kingdom, Switzerland, the United States, Taiwan, and other countries. The majority of them are physicists working at the forefront of synthetic quantum systems. Among them is renowned Professor Reiner Blatt from the University of Innsbruck (Austria), a member of the Lindau Nobel Laureate Meetings Council, who achieved the world's first teleportation of atomic ions and has received numerous prestigious awards for this and other important scientific work.

This year's conference in Lithuania is organizing by a Humboldtian Professor G. Juzeliūnas, along with his colleagues Mažena Mackoit-Sinkevičiene, Domantas Burba, Edvinas Gvozdiovas, Algirdas Mekys, Mantas Račiūnas, and Dzmitry Viarbitski. This is the second Humboldt conference of this kind in Lithuania, the first one was taking place in Vilnius in 2018.

The Humboldt Foundation, which supports science and research, brings together 26,000 Humboldtians who are top specialists from all fields of science from 140 countries. Fifty-one Humboldtians are Nobel Prize laureates. Many Humboldtians are well-known experts in quantum simulations and quantum computing, studying ultracold atoms and ions, and advancing the field of photonics.
The presentations at the Humboldt Kolleg conference will be recorded and made available on the conference website.

Programme

4 July, 17.00. Dr Sara García Alonso, an astronaut and cancer medicine researcher from Spain, will visit Vilnius University Science Communication and Information Centre (Saulėtekio al. 5). She will give a public lecture on "Human spaceflights in the 21st century".

This public lecture is part of the Milky Way - Gaia 3-day school. It will explore new ways to increase inclusiveness in science, to improve the quality of science itself and to increase its impact. The school community, with the support of experts from scientific and social disciplines, will discuss best current practices, learn about possible new initiatives and solutions, speakers will explain how equality, diversity and inclusion are essential to their research.

The event marks the start of the Spanish Presidency of the European Union

The event is organised by the Embassy of Spain in Lithuania in collaboration with the Institute of Theoretical Physics and Astronomy at Vilnius University.

Read more about the MW-Gaia WG5 School here.

"ESA astronaut training"

Photo from www.ESA.int

Congratulations to the Lithuanian team of students who won a gold medal, two silver medals, a bronze medal and a letter of commendation at the 7th European Physics Olympiad in Hanover, Germany, 16-20 June 2023! The gold medal was won by Vilnius Jesuit Gymnasium graduate Tomas Babelis, the silver medals were won by Klaipėda Lyceum graduate Jokūbas Viršilas and Vilnius Lyceum student Paulius Kalinauskas, the bronze medal was won by Kaunas University of Technology Gymnasium graduate Tomas Razbadauskas, and the letter of commendation was awarded to Kaunas University of Technology Gymnasium graduate Dominykas Krasauskas. The team was led by Dr. Jevgenij Chmeliov, associate professor at the Faculty of Physics. Three of the five team members deepened their knowledge of physics by studying at the "Fizikos Olimpas", a school of supplementary education for schoolchildren located at the Faculty of Physics premises.

176 students from 28 European and 10 other countries took part in the Olympiad. During the Olympiad, students competed against each other for two days of 5 hours each, solving experimental and theoretical problems prepared by the organisers of the Olympiad. 

21 June, St. On June 25, 2023 graduates were awarded their Bachelor's and Master's diplomas at St. John's Church. During the celebration, the graduates were greeted by the Vice-Rector of Vilnius University, Professor Edita Sužiedėlienė, the Dean of Vilnius University Faculty of Physics, Aidas Matijošius, and the guest of honour, the Chairman of the Board of the Ekspla Private Limited Liability Company, one of the largest companies of the Lithuanian Laser Association, Dr. Kęstutis Jasiūnas, and the graduate Mantas Auruškevičius.

During the ceremony, three Faculty of Physics BA graduates were awarded one-off nominal scholarships for their special achievements.

500 EUR Dr. Remis Gaška's nominal scholarship for the best Bachelor's thesis was awarded to Mantas Auruškevičius and Domantas Burba.

The aim of this scholarship is to encourage talented students of the Faculty of Physics of Vilnius University to improve their academic performance, participate in research and pursue a career in physics and physical devices. This scholarship is awarded for the best bachelor thesis defended this year. The certificates for this scholarship were presented by Prof. Pranciškus Vitta, Vice Dean for Science and Strategic Development of the Faculty of Physics.

TELE2 Private Limited Liability Company has established a nominal scholarship for the best Bachelor's thesis in the field of Telecommunications and M2M technologies.

The EUR 500 nominal scholarship of UAB TELE 2, intended to encourage talented students of the Faculty of Physics of Vilnius University to achieve better results in their studies, to take part in research in the field of Telecommunications and to pursue a career in the field of Telecommunications and M2M technologies, has been awarded to the graduate of the Faculty of Physics' Bachelor of Continuous Studies in the Electronics and Telecommunications Technologies study programme, Eidvidas Šatkauskas, for the best Bachelor's thesis in the area of telecommunications and M2M technologies. The scholarship certificate was handed over by Julija Tumaitė, HR Business Partner of Tele2 Private Limited Liability Company.

Congratulations to all graduates!

20 June 2023 The Presidium of the Lithuanian Academy of Sciences (LAS), on the basis of the proposals of the expert commissions of the scientific divisions of the LAS for Young Scientists' Fellowships, has awarded 15 fellowships to the best young scientists in the fields of humanities, social sciences, physical sciences, biomedical sciences, technology and agriculture.

For the 2023 LMA Young Scientists Fellowships, 70 applications were submitted: 18 in the humanities and social sciences, 52 in the physical sciences, biomedicine, technology and agriculture. One of these fellowships was awarded to Dr Mantas Šimėnas.

The applications were evaluated by the LMA's panels of experts in the different fields of science. Three fellowships were awarded in each of the humanities and social, physical, biomedical, technological and agricultural sciences. Of these, 3 scholarships were awarded to young scientists from the Lithuanian University of Health Sciences, 2 scholarships were awarded to young scientists from Vilnius, Klaipėda and Vilnius Gediminas Technical Universities and the Centre for Physical Sciences and Technology, and 1 scholarship was awarded to young scientists from Kaunas University of Technology, the National Cancer Institute, the Nature Research Centre, and the Lithuanian Centre of Agrarian and Forest Sciences.

Information from the Lithuanian Academy of Sciences

The first phase of admission to the Master's programme at Vilnius University will continue until 28 June, 10:00 AM.

Light Conversion, a major ultrafast laser technology company, together with the family of late academician Prof. Algis Petras Piskarskas (1942-2022), has made a donation of EUR 200,000 to the Vilnius University Foundation. At the request of the patrons, the donation has created a restricted endowment sub-fund in the name of Prof. Piskarskas, the returns of which will be allocated for the named scholarships to laser physics talents.

Prof. Piskarskas, known as the father of Lithuanian lasers and one of the country's most renowned scientists, has contributed significantly to the fact that Lithuania is today known as the country of laser science. Prof. Piskarskas has devoted a great deal of attention to the strategy of high-tech development and has strived to ensure the international competitiveness of the Lithuanian laser industry. Lithuanian lasers are today exported to more than 40 countries. This success would not have been possible without the contribution of Prof. Piskarskas and his students.

"In addition to creating world-class science and business, Prof. Piskarskas actively supported the idea of the first university’s endowment fund in Lithuania. In 2016, representing the company Light Conversion, Prof. Piskarskas signed the agreement establishing the VU endowment fund. Prof. Piskarskas was also involved in the management of the VU Foundation, advising on key strategic issues. I am glad that Light Conversion and the Piskarskas family are continuing the work started by Prof. Piskarskas," says Justinas Noreika, CEO of the VU Foundation.

According to Justinas Noreika, the newly established sub-fund will be jointly invested with the existing capital of the Foundation, which has grown to EUR 3.6 million with the latest donation. In honor of late Prof. Piskarskas, the returns will be allocated for the named scholarships to the laser science talents of the VU Faculty of Physics, and to fund other scientific activities at Vilnius University.

On the 23rd of March, 2023 An international ELI workshop organised by Vilnius University and the Centre for Physical Sciences and Technology will take place at the Centre for Physical Sciences and Technology A101 auditorium (Saulėtekio av. 3)

Programme

We would like to inform you that the the abstract subbmission deadline to the International Conference for Students of Physics and Natural Sciences ‘Open Readings 2023’ is extended until February 17^th! Do not miss the chance to share your scientific work with students from all around the world. Best posters and oral presentations will be awarded.

Both registration and participation are free of charge!

Register here: https://www.openreadings.eu/registration/

Contact e-mail: 

Do not miss the chance to participate in the 66^th International conference for students of physics and natural sciences ‘Open Readings 2023’!

The registration closes on February 3^rd, 2023.

Register here: https://www.openreadings.eu/registration/

Registration and participation are free of charge!

Every year hundreds of students and young scientists participate in the international science conference ‘Open Readings’, where they have an opportunity to share their scientific research with other students from all around the world. They can also listen to acclaimed invited speakers and scientists who make presentations on various scientific topics (you can find more information about the conference and invited speakers here: https://www.openreadings.eu/).

Students can present posters or give oral presentations about their scientific research. More information about abstract and presentation requirements is here: https://www.openreadings.eu/abstract-and-presentations/

‘Open Readings 2023’ will be held on April 18^th-21^st, 2023, in the Center for Physical Sciences and Technology, in Vilnius, Lithuania. 

Contact information: 

The virtual "Edtech Conference & Hackathon: Education inside Metaverse", which will take place from 22 to 27 November, will bring together visioneers, leaders of technology companies, Lithuanian education policy makers, educators, representatives of the education sector and start-ups in one space. During the Conference, insights will be shared on a brighter and more technologically advanced future for education in the Metaverse, and during the Hackathon participants will develop effective solutions for the future of education.

If you are #EdTech or #Metaverse enthusiast, educator, student or entrepreneur – JOIN EdTech Hackathon & Conference 2022. Get to know, discuss & contribute to Education inside Metaverse!

When? Conference – November 22^nd. Hackathon - November 25^th – 27^th.

Where? Online

What’s in it for me? Cash prize fund of 6000 Eur, building new connections & business knowledge.

Register: https://bit.ly/3UScYjn

More information: https://www.vuhackathon.lt/ 

Event organized by Vilnius University Business School together with Western Union Lithuania and National Agency for Education.

Red Hat Academy is launching a promotion where the first 1,000 students who complete their Red Hat Academy Talent Network profile will receive a free exam voucher for a Preliminary Exam in Red Hat System Administration I! The promotion started October 24th, 2022 and runs through December 31st, 2022.

Requirements and prerequisites

• Must have been enrolled as a student in the Red Hat Academy program
• Completed at least 25% of the Red Hat System Administration I (RH124) course through Red Hat Academy between September 1st, 2020 through October31st, 2022
• Must have a completed student profile on the Red Hat Academy Talent Network, after October 24th, 2022
• Review theRedHat Preliminary Exam in System Administration I (PE124) objectives

For more details, please see the Terms & Conditions. Share and encourage your students to redeem this offer today.

Research on new hybrid materials continues at the Institute of Applied Electrodynamics and Telecommunications.

Recently, hybrid organic-inorganic perovskite materials have aroused great interest as one of the most promising materials for the next generation of photovoltaic modules. The performance of solar cells based on these hybrid compounds is rapidly catching up with traditional inorganic semiconductors and is already above 25%. The highest performance and the best stability of hybrid perovskites are achieved by using mixed-phase compounds, in which part of the crystal components are replaced by cognate components. Despite the very large number of applied studies on such materials, the microscopic aspects of such compounds are not well known.

Here, for the first time, physicists at the VU FF have investigated structural phase transformations and dynamic phenomena in a new type of mixed methylammonium-ethylammonium hybrid perovskites. The phase diagram of these compounds and the influence of mixing on the dynamics and ordering of the molecular cations were determined. This research is expected to lead to the development of more efficient and stable solar cells.

The published research was carried out in collaboration with physicists and chemists from abroad. The crystals were grown by chemists from Poland (Low Temperature and Structure Research of the Polish Academy of Sciences) and the main experiments were carried out in the Microwave Spectroscopy Laboratory of the VU FF. Physicists from Imperial College London also contributed to the research by developing an atomistic model of the processes studied.

The researchers' research has been published in the prestigious American Chemical Society group journal Chemistry of Materials, which has a high citation rate (11).

More information:

Šimėnas et al., "Mixology of MA1-xEAxPbI3 Hybrid Perovskites: Phase Transitions, Cation Dynamics, and Photoluminescence", Chemistry of Materials (2022).

https://pubs.acs.org/doi/10.1021/acs.chemmater.2c02807

Funded by LMT (project S-MIP-22-73).

Physicists of Vilnius University have circumvented Heisenberg’s uncertainty principle and by-passed the Pauli exclusion principle of measuring time in optical clocks more accurately by producing squeezed coherent states in an ultracold fermionic gas.

The research results of the international team with the participation of prof. Gediminas Juzeliūnas, dr. Mažena Mackoit-Sinkevičienė, dr. Giedrius Žlabys (Vilnius University, Faculty of Physics, TFAI), dr. Emilia Witkowska, Tanausu Hernández Yanes (the Institute of Physics PAS, Warsaw) in collaboration with dr. Marcin Płodzień (ICFO, Barcelona) appeared in the prestigious Physical Review Letters. 

The image illustrates the squeezing mechanism in ultra-cold gases of fermionic atoms placed in periodic optical lattices. Credit: Dr. Mazena Mackoit Sinkevičienė, Vilnius University.

UNCERTAINTY PRINCIPLE

The consequence of the quantum nature of objects is the Heisenberg's uncertainty principle, according to which it is impossible to measure, at the same time, all the properties of a quantum particle with any precision: for example, its location and momentum at the same time.

A quantum particle may be in different states. In the so-called coherent state, the uncertainties of measuring its location and momentum are equal. When the particle is in a state in which the uncertainty of one measurement is reduced at the cost of increasing the uncertainty of the other, it is called a squeezed state.A large number of contemporary research projects propose to use quantum effects that allow increasing the precision of measuring a given value, including quantum squeezing.

THE TICKING OF SUPER-ACCURATE CLOCKS

The most accurate clocks use atoms to measure the passage of time - the measurement of the time unit (the second) is based on the measurement of the energy difference between two energy levels, atomic oscillations. In laboratory measurements, atoms, e.g. caesium, are cooled to a temperature close to absolute zero, i.e. the order of nano kelvins, and then based on measuring the difference in the number of atoms in higher and lower energy states, atomic transition frequency is determined. This is the basis for the definition of a modern time unit. In other words, the more accurately we measure the atomic transition frequency, the greater the precision with which we can measure the passage of time. Currently, atomic clocks achieveaprecision of about one-tenth of a nanosecond per day, which means that the atomic clock may be one second late in 300 million years. Scientists are still trying to improve this amazing precision.

WHY DO WE NEED SUCH A PRECISE MEASUREMENT OF TIME?

Professional frequency measurements are very important for the development of science, for example, they allow us to verify the predictions of Einstein's general relativity and the fact that time flows differently depending on the intensity of the gravitational field, which means that time flows differently on Earth than in the satellite orbit, where the GPS satellites are located. The synchronizationof clocks on Earth and in orbit must take this effect into account. A super-accurate clock would also allowthedetectionofgravitational waves and hypothetical dark matter, which can cause slow oscillation of physical constants.

One of the simplest answers concerns the accuracy of GPS systems that we use in our daily lives when we move from one place to another. Proper time synchronization is of fundamental importance here: if the clocks in orbit and on Earth are not synchronized, the GPS system very quickly loses its location accuracy.For example, if the clocks are synchronized at the level of one-hundredth of a second, the accuracy of the position indicated by GPS is about three kilometres.Imagine the consequences of reaching the journey destination located with such accuracy.

To build such super-accurate devices as optical clocks, we need the most accurate information about individual particles. To achieve this precision, however, we need to measure so precisely that we enter the quantum world. This means that the construction of better clocks is hindered by the limits related to Heisenberg's uncertainty principle. Hence, the idea of creating squeezed states appears important to physicists. Simply put, it is about trapping the particles - for example in the lattice of an optical 'cage' - to be able to precisely determine their certain property (atomic transition frequency) at the cost of blurring another property, which will not be important in the target device.

HOW TO PUT FERMIONS IN CONTACT 

Until now, the creation of squeezed states in ultracold atoms was possible with bosonic atoms. Such atoms are able to interact with each other as a result of collisions. For bosons, however, there is a dependence of energetic level shift, the value of which depends mainly on the density of atoms, which in turn means that the accuracy of the atomic transition frequency measurement is significantly reduced. However, the shift of energy levels in fermionic atoms is very limited, which is why fermions are perfect for precise frequency measurements. That is why scientists wanted to produce squeezed states in such atomic gases.This turned out to be a great challenge. The so-called reason was the Pauli exclusion principle that blocked the possibility of mutual interaction of fermionic atoms at temperatures close to absolute zero. As a consequence of the lack of interactions between atoms, it is not possible to generate squeezing. This limitation, however, could be bypassed.

The idea of the teamis that fermions trapped in an optical lattice, in which there is one fermion in a single lattice gap, are illuminated with an external laser light with the appropriate phase. It turns out that the coupling of atoms with light introduces the interaction we need between fermions and generates highly squeezed quantum states. Researchers hope that in the future this idea can be used to increase the accuracy of measuring the frequency of atomic transitions in extremely stable and super-accurate clocks based on fermionic atoms in optical lattices.The method proposed by our physicistsrequires only a small modification of systems currently studied in laboratories, both ultra-cold fermions placed in the periodic optical lattice, as well as the so-called optical tweezers.

Research is financed as part of theLMT S-LL-21-3,NCN DAINA and NAWA BKKER 2020 projects.