Dynamics of strongly interacting Fermi gases with time-dependent interactions: Consequence of conformal symmetry

Abstract

In this Letter, we investigate the effects of a time-dependent, short-ranged interaction on the long-time expansion dynamics of Fermi gases. We show that the effects of the interaction on the dynamics is dictated by how it changes under a conformal transformation, and derive an explicit criterion for the relevancy of time-dependent interactions in both the strongly and non-interacting nearly scale invariant quantum gases. In addition, we show that it is possible to engineer interactions that give rise to non-exponential thermalization dynamics in trapped Fermi gases. To supplement the symmetry analysis, we also perform hydrodynamic simulations to show that the moment of inertia of the trapped gas indeed follows a universal time-dependence determined jointly by the conformal symmetry and time-dependent scattering length $a(t)$. Our results should also be relevant to the dynamics of other systems that are nearly scale invariant and that are governed by a non-relativistic conformal symmetry.

6 pages, 4 figures

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Cited by in corpus (6)

• Hydrodynamic Attractor in Ultracold Atoms
• Complex scaling flows in the quench dynamics of interacting particles
• Emergent Infrared Conformal Dynamics in Strongly Interacting Quantum Gases
• Dynamic virial theorem at nonequilibrium and applications
• Quantum transport in strongly correlated Fermi gases
• Energy Dynamics of a Nonequilibrium Unitary Fermi Gas