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Journal of Physics G Nuclear and Particle Physics

Canonical mean field calculations at finite temperature

R. Rossignoli, H. G. Miller, Angelo Plastino

Published Jul 1, 1991• 3 citations
Publisher

Abstract

A method is proposed to perform canonical mean field calculations at finite temperature. This method can easily be extended to include particular diagonal two-body correlations. The approach is illustrated in an exactly soluble model and exhibits definitive advantages over the conventional finite temperature Hartree-Fock approximation.
DOI
10.1088/0954-3899/17/7/009

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We develop a statistical mean-field theory of finite quantum systems in thermal equilibrium. Our formulation employs the canonical ensemble of statistical mechanics, and it enables us to analytically determine the occupation number distributions of interacting particles obeying Bose–Einstein or Fermi–Dirac statistics. We have also developed a numerical procedure that enables us to obtain a universal scaled occupation number distribution that, for a given total number of interacting particles in a finite system, makes it possible to determine the occupation number distribution for any temperature. The developed mean-field theory is applicable to a wide range of atomic, nuclear and condensed matter systems for which finite-size effects can play an important role. In particular, the present approach makes it possible to formulate a finite temperature mean-field theory for a specific ion in a dense plasma.