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arXiv · 0707.3787

Effective su_q(2) models and polynomial algebras for fermion-boson Hamiltonians

Angel Ballesteros·Osvaldo Civitarese·Francisco J. Herranz·Marta Reboiro
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Abstract

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 q-su(2) of quasifermions. In particular, q-su(2) analogues of the Da Providencia-Schutte 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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Angel Ballesteros, Osvaldo Civitarese, Francisco J. Herranz, Marta Reboiro. 2007-07-25. Effective su_q(2) models and polynomial algebras for fermion-boson Hamiltonians. https://doi.org/10.1023/a%3A1027301616731

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