Fluctuations in the level density of a Fermi gas

P. Leboeuf (1) , A. G. Monastra (2) , A. Relano (3)

1 LPTMS - Laboratoire de Physique Théorique et Modèles Statistiques
2 Institut für Theoretische Physik [Dresden]
3 Departamento de Fisica Atomica, Molecular y Nuclear

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.

Domaines: Physique Nucléaire Théorique [nucl-th]

P. Leboeuf, A. G. Monastra, A. Relano. Fluctuations in the level density of a Fermi gas. Physical Review Letters, 2005, 94, pp.102502. ⟨10.1103/PhysRevLett.94.102502⟩. ⟨hal-00004501⟩