Floquet two-body problem in a harmonic trap

doi:10.3969/j.issn.1000-5641.2024.03.008

Abstract

Abstract:

The dynamics of quantum gases with time-varying interactions have attracted research interests owing to recent advances in experimental techniques such as optical Feshbach resonance. A range of novel dynamic behaviors including the Farady pattern and Bose fireworks have been observed in these systems. In this research, the dynamic problem of two harmonically trapped atoms with periodically modulating interaction strength is investigated. Because of the Hamiltonian time dependence, the system energy is an unconserved quantity. However, we may continue to utilize the Floquet theory for the time-periodic Hamiltonian and define its quasi-energy. The exact equations for the quasi-energies of the two-body problem are derived. Upon numerically solving these equations, we identify that the two-body quasi-energy spectrum exhibits various novel behaviors for different driven parameters or frequencies.

Key words: quantum gases, two-body problem, periodically, quasi-energy

CLC Number:

O562

Dongfan YAN. Floquet two-body problem in a harmonic trap[J]. Journal of East China Normal University(Natural Science), 2024, 2024(3): 73-83.

Figures/Tables 5

References 17

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