Transição de fase Superfluido-Isolante de Mott em redes ópticas via modelo de Jaynes-Cummings-Hubbard

• Ano de defesa: 2013
• Autor(a) principal: Gomes, Clélio Brasil Cardoso
• Orientador(a): Souza, André Maurício Conceição de
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Sergipe
• Programa de Pós-Graduação: Pós-Graduação em Física
• País: BR
• Palavras-chave em Português: Física; Propriedades ópticas; Mecânica quântica; Eletrodinâmica; Superfluido-isolante; Modelo Jaynes-Cummings-Hubbard
• Área do conhecimento CNPq: CNPQ::CIENCIAS EXATAS E DA TERRA::FISICA
• Link de acesso: https://ri.ufs.br/handle/riufs/5338

We study the phase transition super uid-Mott insulator in optical lattices through model Jaynes-Cummings-Hubbard using the fermion approximation. Initially we did a review of the Jaynes-Cummings model that is a model that describes the interaction between an atom with two levels and a quantized electromagnetic eld. Then we stu- died the properties of the phase transition super uid-Mott insulator (SF-MI) through the model Bose-Hubbard and we discuss the characteristics of the two quantum phases and the conditions for phase transition. Apply the model Jaynes-Cummings-Hubbard in order to study the in uence of topology of network Bravais linear, square, single cubic (SC), body-centered cubic (BCC) and face-centered cubic (FCC) in the phase transi- tion SF-MI to different numbers of excitation and different detuning values between the atom and the eld and we found that the Mott lobes and the critical hopping terms are not renormalizable only for the FCC network. But the regime from many excitations, the critical hopping is renormalizable to all networks and is independent of detuning. Then we study the Jaynes-Cummings-Hubbard model for a chain with the addition of the Kerr effect (nonlinear optical effect) through the approximation of fermions (FA). We observed that the Kerr effect does not cause large changes in the energy spectrum. However, the properties of the phase transition SF-MI undergoes signicant changes due to the Kerr effect. Another important feature which has been observed is that the Kerr effect favors the phase MI.