Histerese com múltiplos loops e auto-oscilação induzidas termicamente na fotoluminescência de poços quânticos semicondutores

• Ano de defesa: 2010
• Autor(a) principal: Julia Esteves Parreira
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Minas Gerais; UFMG
• Palavras-chave em Português: Princípio da incerteza de Schrodinger (Mecânica quântica); Cavidade óptica; Sistemas gaussianos bipartidos; Poços quânticos semicondutores; Princípio da incerteza Schrodinger (Mecânica quântica); Física
• Link de acesso: http://hdl.handle.net/1843/ESCZ-8F8HSH

We show that multiloop hysteresis recently observed in semiconductor optical cavities in the strong coupling regime, reported in the references [1] and [2], can be explained as a competition between the externally controlled pumping intensity and the delayed response of the well in delivery the heat to the low of basis. As the external pump intensity grows, the material heats proportionally. However, when the pump intensity decreases, the system cannot deliver heat to the cooled basis at the same rate, and the temperature decreases delayed in relation to the pump intensity. This time mismatch is responsible for the hysteresis and the crossing of the curves. In the reference [2], was showed the existence of self-oscillations with the period much larger then a reasonable value consistent with the coupling constants available in models in the literature. We also show that these self-oscillations have their origin from the same phenomenon. We hope that our simple model, based on all the existent phenomenology about the system, can illuminate a way to amicroscopic dynamic of that system so rich in several aspects of the many body dynamic out of equilibrium.