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Quasiclassical and Statistical Properties of Fermion Systems

M. Grigorescu·W. E. Baylis
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Abstract

A quasiclassical correspondent for the fermion degrees of freedom is obtained by using a time-dependent variational principle with Grassmann coherent states as trial functions. In the real parametrization provided by the canonical coordinates, these states satisfy a closure relationship, and this is used to calculate the partition function at finite temperature. The particular example considered here consists of a many-fermion system in a quantum double-well. Entanglement between the one-particle orbital states leads to deviations from the normal Fermi-Dirac distribution. This deviation is reflected in the dependence of the chemical potential on concentration. In the physical example of two adjacent CuO planes in a high-Tc superconductor, the dependence is suggestive of the pseudogap observed at temperatures T>Tc.

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M. Grigorescu, W. E. Baylis. 2002-01-11. Quasiclassical and Statistical Properties of Fermion Systems. https://doi.org/10.1103/physrevb.66.014530

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