Bulletin of the American Physical Society
52nd Annual Meeting of the APS Division of Atomic, Molecular and Optical Physics
Volume 66, Number 6
Monday–Friday, May 31–June 4 2021; Virtual; Time Zone: Central Daylight Time, USA
Session Q05: Frontiers of SU(N) PhysicsInvited Live
|
Hide Abstracts |
Chair: Richard Scalettar, Davis |
Thursday, June 3, 2021 8:00AM - 8:30AM Live |
Q05.00001: Thermodynamic study of ultracold fermions with SU(N) spin symmetry Invited Speaker: Gyu-boong Jo Advances in AMO techniques enabled the investigation of ultracold fermions with an enlarged SU(N) spin symmetry, and offered unique possibilities for exploring correlated quantum many-body systems with high spin. In such a fermionic system of ultracold two-electron atoms of ytterbium-173, multi-component fermions interact identically with others due to SU(N) symmetry with tunable N=1,...,6. In this talk, we report our progress toward a quantitative thermodynamic study of SU(N) fermions, including experiments on measuring compressibility, revealing bosonization and investigating collective excitations. These developments, together with recent experiments from other groups, set the stage for exploring SU(N) spin symmetry in the context of magnetic correlations both in bulk and lattices. |
Thursday, June 3, 2021 8:30AM - 9:00AM Live |
Q05.00002: Suppression and Control of Prethermalization in Multicomponent Fermi gases Following a Quantum Quench Invited Speaker: Miguel A Cazalilla We investigate the mechanisms of control and suppression of prethermalization focusing on N-component alkaline-earth-like gases. Using time-dependent perturbatition theory, we compute the short-time dynamics of the instantaneous momentum distribution and the relative population for different initial conditions after an interaction quench, accounting for the effect of initial interactions. We find that switching on an interaction that breaks the SU(N) symmetry of the initial Hamiltonian, thus allowing for the occurrence of spin-changing collisions, does not necessarily lead to a suppression of prethermalization. However, the suppression will be most effective in the presence of SU(N)-breaking interactions provided the number of components N≥4 and the initial state contains a population imbalance that breaks the SU(N) symmetry. We also find the conditions on the imbalance initial state that allow for a prethermal state to be stabilized for a certain time. Our study highlights the important role played by the initial state in the prethermalization dynamics of multicomponent Fermi gases. It also demonstrates that alkaline-earth-metal Fermi gases provide an interesting playground for the study and control of prethermalization. |
Thursday, June 3, 2021 9:00AM - 9:30AM Live |
Q05.00003: SU(N) spin symmetry and optical atomic clocks Invited Speaker: Jun Ye The state-of-the-art precision of a Sr optical lattice clock was used to measure SU(N) symmetrical interactions among 10 nuclear spin states in fermionic 87Sr, providing a convenient platform to observe non-equilibrium spin-orbital dynamics in SU(N) magnetism [1]. Meanwhile, by creating arrays of isolated few-body systems of 87Sr in a 3D optical lattice, high resolution clock spectroscopy revealed the onset of both elastic and inelastic multi-body interactions, highlighting the emergence of multi-body interactions in two-orbital high-spin fermions with SU(N) symmetry [2]. SU(N) symmetry also represents an untapped resource for cooling due to large s-wave collision rates and absence of spin loss, allowing us to produce deeply degenerate Fermi gases in just 0.6 s after initial laser cooling [3]. While this provides a precise study of the thermodynamics of a deeply degenerate Fermi gas with SU(N)-symmetric interactions, the fast preparation of quantum matter is also crucial for the advancement of 3D optical lattice clocks and has facilitated our recent observation of Pauli blocking of spontaneous radiative decay [4]. |
Thursday, June 3, 2021 9:30AM - 10:00AM Live |
Q05.00004: Correlations and Universality in Ultracold Alkaline Earth Atoms Invited Speaker: Kaden R Hazzard Ultracold alkaline-earth fermions in an optical lattice realize the famous Hubbard model from solid-state physics, but with spins tunable to be as large as $S=9/2$, instead of the usual $S=1/2$. Although $S$ can be large, the system remains non-classical due to an enlarged SU($N$) interaction symmetry that protects quantum fluctuations and leads to new phases of matter. However, just as for the $N=2$ Hubbard model, it has remained an outstanding challenge for cold atoms experiments to achieve temperatures low enough to observe phenomena such as superconductivity and magnetic order. I will describe how enlarging SU(2) to SU($N$) not only enriches the physics, but lowers the temperature and increases magnetic correlations, as recently observed by the Kyoto group [1] in 1D, 2D, and 3D. Our calculations agree with the measurements in broad regimes. This allows thermometry, showing that the experiments in 1D have produced the coldest fermions ever achieved. The calculations also reveal surprising universality in the equations of state, pointing to simple underlying physics. Finally, I will describe important future directions for understanding longer range correlations and dynamics. |
Follow Us |
Engage
Become an APS Member |
My APS
Renew Membership |
Information for |
About APSThe American Physical Society (APS) is a non-profit membership organization working to advance the knowledge of physics. |
© 2024 American Physical Society
| All rights reserved | Terms of Use
| Contact Us
Headquarters
1 Physics Ellipse, College Park, MD 20740-3844
(301) 209-3200
Editorial Office
100 Motor Pkwy, Suite 110, Hauppauge, NY 11788
(631) 591-4000
Office of Public Affairs
529 14th St NW, Suite 1050, Washington, D.C. 20045-2001
(202) 662-8700