# CMT Seminar: Classical-field methods for finite-temperature Bose gases

Monday, June 27, 2011 – 3:15pm

Reiss 502

Tod Wright

School of Mathematics and Physics, University of Queensland

Partially-condensed degenerate Bose gases can exhibit complicated non-equilibrium superfluid behavior, which constitutes a strong challenge for theoretical description. In typical experiments with dilute gaseous Bose condensates, the multi-mode, interacting nature of the Bose field is much more significant than the quantum fluctuations encoded in the field operator commutation relations, and very accurate descriptions of the system behavior in both equilibrium and non-equilibrium regimes can be obtained from a classical ergodic or stochastic description. In this talk, after briefly reviewing the basic theory of degenerate Bose gases and Bose-Einstein condensation, I will introduce the classical-field approximation for these systems, and discuss its utility in the description of finite-temperature superfluid dynamics. I will discuss the relationship between the classical-field formalism and more traditional theoretical methods for the degenerate Bose gas, and present results on coherence and superfluidity in low-dimensional systems, and finite-temperature non-equilibrium superfluid and vortex dynamics, obtained in the classical-field approach.

Host: Marcos Rigol