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Updated: Apr 25, 2026

An Analog Macroscopic Technique for Studying Molecular Hydrodynamic Processes in Dense Gases and Liquids
Published on: December 4, 2017
Stochastic Gross-Pitaevskii equation for the dynamical thermalization of Bose-Einstein condensates
I G Savenko1, T C H Liew2, I A Shelykh1
1Science Institute, University of Iceland, Dunhagi 3, IS-107 Reykjavik, Iceland and Division of Physics and Applied Physics, Nanyang Technological University, 637371 Singapore, Singapore.
Abstract:
We present a theory for the description of energy relaxation in a nonequilibrium condensate of bosonic particles. The approach is based on coupling to a thermal bath of other particles (e.g., phonons in a crystal, or noncondensed atoms in a cold atom system), which are treated with a Monte Carlo type approach. Together with a full account of particle-particle interactions, dynamic driving, and particle loss, this offers a complete description of recent experiments in which Bose-Einstein condensates are seen to relax their energy as they propagate in real space and time. As an example, we apply the theory to the solid-state system of microcavity exciton polaritons, in which nonequilibrium effects are particularly prominent.
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