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Modern Physics Letters A

Finite Temperature SU(2) LMG Model: Mean-Field Versus Exact Calculation

L. Brito, Constança Providência, João da Providência

Published Dec 14, 1997• 3 citations
Publisher

Abstract

A variational approach is applied to the description of temperature effects in an N-particle exactly solvable schematic model, with SU(2) symmetry. The ground-state energy and the strength distribution for different couplings and temperatures are compared with the exact results.
DOI
10.1142/s0217732397003101

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The interplay between pairing and shape deformations at finite temperatures is studied with reference to an exactly soluble SU(2)\ifmmode\times\else\texttimes\fi{}SU(2) model which is able to suitably mock up both superconductivity and the effects of long-range residual forces. Thermodynamic and ground state phase transitions are studied, both in the thermodynamic limit and in the case of a finite number of particles. Several independent quasiparticle approximations are analyzed with reference to the corresponding exact results.
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