Classical dynamics of harmonically trapped interacting particles. (18th June 2018)

• Record Type: Journal Article
• Authors: Dong, Zhiyu; Moessner, Roderich; Haque, Masudul
• Is Part Of: Journal of statistical mechanics. (2018:Jun.)
• Publication Date: 2018-06-18
• Subjects: 9 -- 4 -- 2 -- 3; Statistical mechanics -- Periodicals; Mechanics -- Statistical methods -- Periodicals; 530.1305
• DOI: 10.1088/1742-5468/aac741
• Languages: English
• ISSNs: 1742-5468

Abstract

Abstract: Motivated by current interest in the dynamics of trapped quantum gases, we study the microcanonical dynamics of a trapped 1D gas of classical particles interacting via a finite-range repulsive force of tunable strength. We examine two questions whose analogues 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.