Anharmonicity effects in the bosonic U(2)-SO(3) excited-state quantum phase transition

We study the effect of the inclusion of the U(2) Lie algebra second-order Casimir operator in a model Hamiltonian of the vibron model two-dimensional limit. We extend previously published results, showing that the inclusion of the additional term does not alter the ground-state quantum phase transit...

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Detalhes bibliográficos
Autores: Pérez Bernal, Francisco, Álvarez Bajo, Osiris
Formato: artículo
Fecha de publicación:2010
País:España
Recursos:Universidad de Huelva (UHU)
Repositorio:Arias Montano. Repositorio Institucional de la Universidad de Huelva
Idioma:inglés
OAI Identifier:oai:ariasmontano.uhu.es:10272/8008
Acesso em linha:http://hdl.handle.net/10272/8008
Access Level:acceso abierto
Palavra-chave:Boson models
Quantum phase transitions
Descrição
Resumo:We study the effect of the inclusion of the U(2) Lie algebra second-order Casimir operator in a model Hamiltonian of the vibron model two-dimensional limit. We extend previously published results, showing that the inclusion of the additional term does not alter the ground-state quantum phase transition between the symmetric and deformed limits of the model. Nevertheless, the inclusion of this operator implies deep changes on the excitation spectrum and on the ensuing excited-state quantum phase transitions.