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arXiv · 1009.2125

Dynamics of quantum quenching for BCS-BEC systems in the shallow BEC regime

Abstract

The problem of coupled Fermi-Bose mixtures of an ultracold gas near a narrow Feshbach resonance is approached through the time-dependent and complex Ginzburg-Landau (TDGL) theory. The dynamical system is constructed using Ginzburg-Landau-Abrikosov-Gor'kov (GLAG) path integral methods with the single mode approximation for the composite Bosons, and the equilibrium states are obtained in the BEC regime for adiabatic variations of the Feshbach detuning along the stationary solutions of the dynamical system. Investigations into the rich superfluid dynamics of this system in the shallow BEC regime yields the onset of multiple interference patterns in the dynamics as the system is quenched from the deep-BEC regime. This results in a partial collapse and revival of the coherent matter wave field of the BEC, whose temporal profile is reported.

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Analabha Roy. 2010-09-11. Dynamics of quantum quenching for BCS-BEC systems in the shallow BEC regime. https://doi.org/10.1140/epjp/i2012-12034-x

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