Broken scale-invariance in time-dependent trapping potentials

Abstract

The response of a cold atom gas with contact interactions to a smoothly varying external harmonic confinement in the non-adiabatic regime is studied. The time variation of the angular frequency is varied such that the system is, for vanishing or infinitely strong contact interactions, scale invariant. The time evolution of the system with broken scale invariance (i.e., the time evolution of the system with finite interaction strength), is contrasted with that for a scale invariant system, which exhibits Efimovian-like expansion dynamics that is characterized by log-periodic oscillations with unique period and amplitude. It is found that the breaking of the scale invariance by the finiteness of the interactions leads to a time dependence of the oscillation period and amplitude. It is argued, based on analytical considerations for atomic gases of arbitrary size and numerical results for two one-dimensional particles, that the oscillation pe riod approaches that of the scale-invariant system at large times. The role of the time-dependent contact in the expansion dynamics is analyzed.

9 pages, 5 figures

References in corpus (7)

• Theory of ultracold Fermi gases
• Experimental Observation of a Generalized Gibbs Ensemble
• Ultrafast many-body interferometry of impurities coupled to a Fermi sea
• Energetics and Structural Properties of Trapped Two-Component Fermi Gases
• High-fidelity rapid ground-state loading of an ultracold gas into an optical lattice
• How does an interacting many-body system tunnel through a potential barrier to open space?
• Ballistic quench-induced correlation waves in ultracold gases

Cited by in corpus (9)

• Few-body Bose gases in low dimensions -- a laboratory for quantum dynamics
• Density Oscillations Induced by Individual Ultracold Two-Body Collisions
• Static and dynamic properties of a few spin $1/2$ interacting fermions trapped in an harmonic potential
• Non-Perturbative Dynamical Effects in Nearly Scale Invariant Systems: The Action of Breaking Scale Invariance
• Dynamics of strongly interacting Fermi gases with time-dependent interactions: Consequence of conformal symmetry
• Effective self-similar expansion of a Bose-Einstein condensate: Free space vs confined geometries
• Dynamics of small trapped one-dimensional Fermi gas under oscillating magnetic fields
• Dynamic virial theorem at nonequilibrium and applications
• Dynamical resistivity of a few interacting fermions to the time-dependent potential barrier