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Fluctuations in the level density of a Fermi gas

P. Leboeuf·A. G. Monastra·A. Relano
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Abstract

We present a theory that accurately describes the counting of excited states of a noninteracting fermionic gas. At high excitation energies the results reproduce Bethe's theory. At low energies oscillatory corrections to the many--body density of states, related to shell effects, are obtained. The fluctuations depend non-trivially on energy and particle number. Universality and connections with Poisson statistics and random matrix theory are established for regular and chaotic single--particle motion.

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P. Leboeuf, A. G. Monastra, A. Relano. 2004-11-17. Fluctuations in the level density of a Fermi gas. https://doi.org/10.1103/physrevlett.94.102502

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