Dynamical thermalization of Bose-Einstein condensate in Bunimovich stadium
1 Departamento de Física, Gerencia de Investigación y Aplicaciones, Comisión Nacional de Energía Atómica Av. del Libertador 8250, 1429 Buenos Aires, Argentina
2 Laboratoire de Physique Théorique du CNRS (IRSAMC), Université de Toulouse, UPS F-31062 Toulouse, France
Received: 18 May 2015
Accepted: 28 August 2015
We study numerically the wave function evolution of a Bose-Einstein condensate in a Bunimovich stadium billiard being governed by the Gross-Pitaevskii equation. We show that for a moderate nonlinearity, above a certain threshold, there is emergence of dynamical thermalization which leads to the Bose-Einstein probability distribution over the linear eigenmodes of the stadium. This distribution is drastically different from the energy equipartition over oscillator degrees of freedom which would lead to the ultra-violet catastrophe. We argue that this interesting phenomenon can be studied in cold-atom experiments.
PACS: 05.45.-a – Nonlinear dynamics and chaos / 05.45.Mt – Quantum chaos; semiclassical methods / 67.85.Hj – Bose-Einstein condensates in optical potentials
© EPLA, 2015