Análise crítica da dinâmica de uma cavidade pendular quântica

• Ano de defesa: 2004
• Autor(a) principal: Melo, Andrea Barroso
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal Fluminense; Programa de Pós-graduação em Física; Física; BR; UFF
• Palavras-chave em Português: Optica quântica; Processos estocásticos; Teoria das representações; Equações de Fokker-Planck; Quantum optics; Stochastic process; Fokker-Planck equations; CNPQ::CIENCIAS EXATAS E DA TERRA::FISICA::FISICA DA MATERIA CONDENSADA
• Link de acesso: https://app.uff.br/riuff/handle/1/21137

We perform a quantum mechanical analysis of a pendular cavity, using the positive-P representation, showing that the quantum state of the moving mirror, a microscopic object, has noticeable e®ects on the dynamics. This system was previously been proposed as a candidate for the quantum-limited measurement of small displacements os the mirror due to radiation pressure, for the production of states with entanglement between the mirror and the field, and even for superposition states of the mirror. However, when we treat the oscillating mirror quantum mechanically, we find that it always oscillates, has no stationary steady-state, and exhibits uncertainties in position and momentum wich are typically large than the mean values. This means that previous linearised fluctuation analyses wich have been used to predict these highly quantum states are of limited use. We find that achievable accuracy in measurement is far worse than the standard quantum limit due to thermal noise, which, for typical experimental parameters, is overwhelming even at 2mK