On the next Monday, the 14th of March, at 4.30 p.m., Jerzy Pniewski and Leopold Infeld Colloquium of the Faculty of Physics of the University of Warsaw will take place. The meeting will be exclusively online (registration required).

Our guest will be Professor Chris Westbrook from the Laboratoire Charles Fabry de l'Institut d'Optique, Palaiseau, France, who will give a lecture: "Quantum atom optics using pair correlation measurements".

An atomic Bose-Einstein condensate is formed when, above a certain critical density, a group of atoms adopt the same quantum state and occupy macroscopically the state with the lowest available energy. Since an ultra-low temperature is required for the transition to the condensed state, the possibility of obtaining it did not seem feasible for a long time. In this talk, we will learn how atomic condensates are obtained and
studied using optical methods - in particular correlations of single photons.

Registration:

• Those who registered for the Seminar on 13.12.2021 or 17.01.2022 do NOT have to register again.
  These attendees will receive a reminder on the day of the Seminar with a link allowing them to participate in the lecture.
• Those who did not attend the previous Colloquium are asked to register for the meeting by clicking on the link: https://us02web.zoom.us/meeting/register/tZIpcOuurDwoHtKL-lYSDQP7e_bd31iTMbhx. After registering you will receive an e-mail confirmation with information on how to join the meeting.
• We strongly recommend providing professional email addresses, not private ones, when registering.
• We encourage you not to leave registration to the last minute. Those who register late will not be guaranteed to join the meeting on time.

For informal discussions, please join us starting at 4 pm.

With best regards,
Barbara Badełek
Jan Chwedeńczuk
Jan Kalinowski
Jan Suffczynski

Chris Westbrook
Laboratoire Charles Fabry de l'Institut d'Optique,
Palaiseau, France
"Quantum atom optics using pair correlation measurements"

Since the demonstration of Bose-Einstein condensation almost 30 years ago, the study of interacting degenerate quantum gases in various configurations has occupied many researchers. The nature of pair correlations in such systems has played a central role and recent years have seen many experiments on this topic. In this talk, I will discuss the use of spatially and temporally resolved detectors to observe 2 particle and even multi-particle correlations. The talk will cover the Hanbury Brown-Twiss effect, the Hong-Ou Mandel effect and the investigation of quantum depletion in a Bose-Einstein condensate.