Dinâmica coerente de estados quânticos em nanoestruturas semicondutoras acopladas

• Ano de defesa: 2014
• Autor(a) principal: Borges, Halyne Silva
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Uberlândia; BR; Programa de Pós-graduação em Física; Ciências Exatas e da Terra; UFU
• Palavras-chave em Português: Pontos quânticos semicondutores; Tunelamento; Éxcitons; Transparência induzida; Controle coerente; Emaranhamento; Pontos quânticos; Semicondutores - Propriedades óticas; Tunelamento (Física); Semiconductors quantum dots; Tunneling; Induced transparency; Coherent control; Entanglement; CNPQ::CIENCIAS EXATAS E DA TERRA::FISICA
• Link de acesso: https://repositorio.ufu.br/handle/123456789/15615; https://doi.org/10.14393/ufu.te.2014.90

In this work we investigate theoretically the dissipative dynamics of exciton states in a system constituted by coupled quantum dots, which in turn exhibit a great flexibility and experimental ability to change their energy spectrum and structural geometry through of external electric fields. In this way, the optical coherent control of charge carriers enables the investigation of several quantum interference process, such as tunneling induced transparency. We investigate the optical response of the quantum dot molecule considering different optical regimes and electric field values, where the tunneling between the dots can establish efficiently quantum destructive interference paths causing significant changes on the optical spectrum. Using realistic experimental parameters we show that the excitons states coupled by tunneling exhibit a controllable and enriched optical response. In this system, we also investigate the entanglement degree between the electron and hole, and we demonstrate through of the control of parameters such as, the applied gate voltage, the incident laser frequency and intensity, the system goes to an asymptotic state with a high entanglement degree, which is robust to decoherence process.