arXiv:2310.03250 · Springer proceedings in physics

Simulation Method for Evaporative Cooling of Trapped Bose Gases at Finite Temperatures

Emiko Arahata, Tetsuro Nikuni

Published Jan 1, 2026• 0 citations

Abstract

Abstract We have devised a simulation method for studying the evaporative cooling process of trapped Bose-Einstein condensates at finite temperatures, leveraging the Zaremba-Nikuni-Griffin (ZNG) formalism. This framework incorporates the generalized Gross-Pitaevskii (GP) equation and a semiclassical kinetic equation governing the behavior of the thermal cloud. Our approach builds upon the numerical techniques pioneered by Jackson and Zaremba, which involve simulating the kinetic equation using test particles. A pivotal aspect of our method lies in emulating the evaporative cooling process by selectively removing test particles with high energy. Through extensive simulations, we demonstrate the efficacy of our approach in accurately describing condensate growth during evaporative cooling. Furthermore, we extend our simulations to investigate the formation of vortex lattices during evaporative cooling in the presence of a rotating thermal cloud. This comprehensive analysis provides valuable insights into the intricate dynamics of trapped Bose-Einstein condensates undergoing evaporative cooling processes.

DOI: 10.1007/978-981-92-0844-9_10

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