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arXiv · 1205.6758

Thermalization in one- plus two-body ensembles for dense interacting boson systems

N. D. Chavda·V. K. B. Kota·V. Potbhare
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Abstract

Employing one plus two-body random matrix ensembles for bosons, temperature and entropy are calculated, using different definitions, as a function of the two-body interaction strength \lambda for a system with 10 bosons (m=10) in five single particle levels (N=5). It is found that in a region \lambda \sim \lambda_t, different definitions give essentially same values for temperature and entropy, thus defining a thermalization region. Also, (m,N) dependence of \lambda_t has been derived. It is seen that \lambda_t is much larger than the \lambda values where level fluctuations change from Poisson to GOE and strength functions change from Breit-Wigner to Gaussian.

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N. D. Chavda, V. K. B. Kota, V. Potbhare. 2012-05-30. Thermalization in one- plus two-body ensembles for dense interacting boson systems. https://doi.org/10.1016/j.physleta.2012.08.054

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