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Progress of Theoretical Physics

Schwinger-Type Boson Realization for the su(4) Algebra: In Relation to the Description of Many-Fermion Systems in Pairing Correlation

M. Yamamura, A. Kuriyama, Teiji Kunihiro

Published Aug 1, 2000• 0 citations
Publisher

Abstract

Considering the present situation of Lie-algebraic studies of high-temperature superconductivity, a Schwinger-type boson realization of the su(4) algebra is investigated. The basic framework comes from a possible form of the su(n) and the su(n,1) algebras in the Schwinger representation, which was recently proposed by two of the present authors (M. Y. & A. K.), together with J. da Providência. The form investigated in this paper is, in some sense, a natural extension of the Schwinger boson representation for the so(5), so(4) and su(2)⊗su(2) algebras, which was also proposed by the present authors. The orthogonal set for the irreducible representation of the su(4) algebra is completely analogous to that expressed in terms of fermion operators for pairing correlation.

DOI
10.1143/ptp.104.401

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