Trapping-potential dependence of the unitary Fermi gas at the BCS-BEC crossover
Adèle Le Borgne (University of Bern)
| Fri May 15, 07:00-08:00 (2 days from now) | |
Abstract: Cold-atom experiments which measure Fermi-gas properties near unitarity confine fermionic atoms to a region of space using trapping potentials of various shapes. The presence of a trapping potential introduces a new characteristic physical scale in the superfluid EFT which, inter alia, describes the acoustic branch of excitations in the far infrared well below the scale of the superfluid gap. In this EFT there is a clear hierarchy of scales, and corrections to the homogeneous system due to the trapping potential may be organized into three regions with distinct power counting that relies on both the EFT derivative expansion, and the WKB approximation, which is an expansion in gradients of the trapping potential. The energy spectrum of the superfluid system is obtained in each of the regions by explicit computation of the phonon-field fluctuations, and by the modifications to the dynamic structure factor due to the corresponding density fluctuations. The most significant deviations from linear dispersion due to the trapping potential are found in the far infrared region of the superfluid EFT.
condensed mattergeneral relativity and quantum cosmologyHEP - theorymathematical physicsdifferential geometry
Audience: advanced learners
Europe and Pacific Theoretical Physics
Series comments: European and Pacific Theoretical Physics is a group that runs online seminars and talks across broad topics in mathematical and theoretical physics. Our goal is to share concepts across continents to bring about a deeper understanding of cutting-edge topics in physics.
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| Organizers: | Jesse Woods*, Jonathan Skelton*, Adèle Le Borgne, Bart Pyszkowski, Joey Faller |
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