Transporte e emaranhamento em fios quânticos desordenados: simulação numérica via método de Monte Carlo

• Autor(a) principal: COSTA, José Eduardo Tributino
• Data de Publicação: 2020
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Biblioteca Digital de Teses e Dissertações da UFRPE
• Texto Completo: http://www.tede2.ufrpe.br:8080/tede2/handle/tede2/9369
• topic: Física mesoscópica; Transporte eletrônico; Nanofios; Emaranhamento quântico; Método de Monte Carlo; Método Tight-Binding; CIENCIAS EXATAS E DA TERRA::FISICA

In this work we study transport properties in disordered quantum wires coupled to electron reservoirs by ideal leads. Specifically, we study the statistical properties of conductance using the DMPK equation, which describes the time evolution of the joint distribution of transmission eigenvalues as a function of the wire length. For this, we used the Monte Carlo method presented in reference [1] for the approximate solution of the DMPK equation in the metallic regime, which is valid in all Wigner-Dyson symmetry classes. Thus, we investigate mesoscopic phenomena such as weak localization and universal conductance fluctuations, as well as the complete distribution of the conductance in the crossover region between the metallic and localized regimes. Furthermore, we investigated the proposal of a quantum wire as a producer of non-interacting electron entanglement introduced in reference [2]. In this case we extended the Monte Carlo method to study the statistical properties of the concurrence. All the obtained results were supported by simulations of disordered quantum wires based on a tight-binding model.