Effective suq(2) models and polynomial algebras for fermion-boson Hamiltonians
نویسنده
چکیده
Schematic su(2)⊕ h3 interaction Hamiltonians, where su(2) plays the role of the pseudo-spin algebra of fermion operators and h3 is the Heisenberg algebra for bosons, are shown to be closely related to certain nonlinear models defined on a single quantum algebra suq(2) of quasifermions. In particular, suq(2) analogues of the Da ProvidenciaSchütte and extended Lipkin models are presented. The connection between q and the physical parameters of the fermion-boson system is analysed, and the integrability properties of the interaction Hamiltonians are discussed by using polynomial algebras.
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