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Quantum Chaos of Bogoliubov Waves for a Bose-Einstein Condensate in Stadium Billiards

Chuanwei Zhang·Jie Liu·Mark G. Raizen·Qian Niu
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Abstract

We investigate the possibility of quantum (or wave) chaos for the Bogoliubov excitations of a Bose-Einstein condensate in billiards. Because of the mean field interaction in the condensate, the Bogoliubov excitations are very different from the single particle excitations in a non-interacting system. Nevertheless, we predict that the statistical distribution of level spacings is unchanged by mapping the non-Hermitian Bogoliubov operator to a real symmetric matrix. We numerically test our prediction by using a phase shift method for calculating the excitation energies.

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Chuanwei Zhang, Jie Liu, Mark G. Raizen, Qian Niu. 2004-06-18. Quantum Chaos of Bogoliubov Waves for a Bose-Einstein Condensate in Stadium Billiards. https://doi.org/10.1103/physrevlett.93.074101

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