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arXiv · 1712.08025

Classical Dynamics of Harmonically Trapped Interacting Particles

Zhiyu Dong·R. Moessner·Masudul Haque
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Abstract

Motivated by current interest in the dynamics of trapped quantum gases, we study the microcanonical dynamics of a trapped one-dimensional gas of classical particles interacting via a finite-range repulsive force of tunable strength. We examine two questions which have been of interest in quantum dynamics: (1) the breathing mode (size oscillation) dynamics of the trapped gas and the dependence of the breathing frequency on the interaction strength, and (2) the long-time relaxation and possible thermalization of the finite isolated gas. We show that the breathing mode frequency has non-monotonic dependence on the magnitude of the mutual repulsion, decreasing for small interactions and increasing for larger interactions. We explain these dependences in terms of slowing-down or speeding-up effects of two-body collision processes. We find that the gas thermalizes within a reasonable finite timescale in the sense of single-particle energies acquiring a Boltzmann distribution, only when the interaction strength is large compared to the energy per particle.

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BibTeXRIS

Zhiyu Dong, R. Moessner, Masudul Haque. 2017-12-21. Classical Dynamics of Harmonically Trapped Interacting Particles. https://doi.org/10.1088/1742-5468/aac741

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