EXCITAÇÃO PARAMÉTRICA QUÂNTICA EM MODOS ACOPLADOS

The problem of so-called "quantum teleportation", or a transfer of the state of some quantum system to another quantum system has attracted attention of many authors. The aim of our study is to consider the effect of the quantum parametric excitation on the quantum information exchange bet...

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Detalles Bibliográficos
Autor: Lara, Lucas Stori de
Tipo de recurso: tesis de maestría
Estado:Versión publicada
Fecha de publicación:2007
País:Brasil
Institución:Universidade Estadual de Ponta Grossa (UEPG)
Repositorio:Biblioteca Digital de Teses e Dissertações da UEPG
Idioma:portugués
OAI Identifier:oai:tede2.uepg.br:prefix/846
Acceso en línea:http://tede2.uepg.br/jspui/handle/prefix/846
Access Level:acceso abierto
Palabra clave:emaranhamento
compressão
correlações quânticas
excitação paramétrica
escalas múltiplas
entanglement
squeezing
quantum correlations
parametric excitation
multiple scales
CNPQ::CIENCIAS EXATAS E DA TERRA::FISICA
Descripción
Sumario:The problem of so-called "quantum teleportation", or a transfer of the state of some quantum system to another quantum system has attracted attention of many authors. The aim of our study is to consider the effect of the quantum parametric excitation on the quantum information exchange between two modes of the electromagnetic field modeled by coupled quantum oscillators, where one of the oscillators has a time dependent frequency, as an extension of the case of two coupled modes considered. In the quantum case, the oscillators exchange not only energies, but also their quantum states and such an exchange can be interpreted as an ideal information transfer. We see that the possibility of quantum state exchange or information transfer can be detected in the most direct way by analyzing the Schrödinger propagator features in the coordinate representation. There are many different schemes of calculating the propagators of coupled oscillators, but the simplest one is that based on the theory of linear time dependent quantum invariants. Considering that the system in study models the coupled modes of the electromagnetic field, the interaction occurs in the domain of the weak interactions; the intensity of the coupling constants are small. Then we can consider the systems of differential equations for the dynamic behavior in the case of weak coupling limit. Starting with this argument, we can reduce the differential equations of first order to the only two groups of second order differential equations for all that ¸’s matrices. With the ¸’s matrices well determined, we can calculate the measured of entanglement, squeezing, purity and other quantum state properties of each mode in a particular case of Gaussian initial states.