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Chinese Physics Letters

SU(2) × SU(2) quasi-spin model and constrained Hartree-Fock method

Liao Ji-Zhi

Published Jun 1, 1990• 2 citations
Publisher

Abstract

In order to study the effectivity for the constrained Hartree-Fock (CHF) method, a quasi-spin model containing two kinds of interaction is proposed. The exact solution of the model Hamiltonian in SU(2) × SU(2) basis, the HF and some CHF solutions as well as the ground state phase transition are discussed.
DOI
10.1088/0256-307x/7/6/005

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We test the coherent correlated pair method with the soluble SU(3) Hamiltonian of Li, Klein, and Dreizler. We compare the results for the ground state energy with the exact solution and with the Hartree-Fock results as a function of coupling parameters and number of particles. For all cases the coherent correlated pair method yields the better upper bound to the ground state energy.NUCLEAR STRUCTURE Correlated pairs; coherent states; upper bounds to ground state energies; applications to exactly soluble SU(3) NNN-fermion model.
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