Máquina térmica quântica operando entre reservatórios de defasagem

• Ano de defesa: 2024
• Autor(a) principal: Bernardo, Amanda Moreira
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Mato Grosso; Brasil; Instituto de Física (IF); UFMT CUC - Cuiabá; Programa de Pós-Graduação em Física
• Palavras-chave em Português: Máquina térmica quântica; Ciclo de Otto quântico; Defasagem pura; Defasagem local; Sistemas quânticos abertos; CNPQ::CIENCIAS EXATAS E DA TERRA::FISICA; Quantum thermal machine; Quantum Otto cycle; Pure dephasing; Local dephasing
• Link de acesso: http://ri.ufmt.br/handle/1/6594

In this master’s dissertation, we propose a model for a quantum thermal machine operating an Otto cycle between local dephasing reservoirs. The working substance consists of a quantum system with two interacting sites. The dynamics of the working substance coupled to a dephasing thermal reservoir were deduced from a microscopic model, resulting in a Markovian master equation. Through coherent coupling between the two sites, we demonstrate that a local dephasing reservoir generates dissipative effects, in addition to the loss of quantum coherence. Consequently, it was possible to implement the isochoric processes that form the Otto cycle. We show that the thermalization time associated with these processes can be adjusted by varying the parameters of the two-site system. In cases where no thermalization occurs, the Otto cycle does not operate ideally, leading to a reduction in the efficiency of the thermal machine. However, we demonstrate that in such cases, ideal efficiency can be achieved as we increase the number of cycles executed by the thermal machine.