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arXiv · 1803.07459

Prethermalization to thermalization crossover in a dilute Bose gas following an interaction ramp

Mathias Van Regemortel·Hadrien Kurkjian·Iacopo Carusotto·Michiel Wouters
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Abstract

The dynamics of a weakly interacting Bose gas at low temperatures is close to integrable due to the approximate quadratic nature of the many-body Hamiltonian. While the short-time physics after an abrupt ramp of the interaction constant is dominated by the integrable dynamics, integrability is broken at longer times by higher-order interaction terms in the Bogoliubov Hamiltonian, in particular by Beliaev-Landau scatterings involving three quasiparticles. The two-stage relaxation process is highlighted in the evolution of local observables such as the density-density correlation function: a dephasing mechanism leads the system to a prethermal stage, followed by true thermalization conveyed by quasiparticle collisions. Our results bring the crossover from prethermalization to thermalization within reach of current experiments with ultracold atomic gases.

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Mathias Van Regemortel, Hadrien Kurkjian, Iacopo Carusotto, Michiel Wouters. 2019-01-15. Prethermalization to thermalization crossover in a dilute Bose gas following an interaction ramp. https://doi.org/10.1103/physreva.98.053612

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