Nonlinear Dynamics in Semiconductor Lasers - Abstract
Virte, Martin
Using quantum dot as the active region of laser systems has been a big advance in laser technology. Although these devices exhibit very exciting features like very low threshold or enhanced stability, their dynamic remain somehow unclear. In a quantum dot laser, multiple states can be confined and we can then observe lasing not only from recombination of ground-state (GS) but also of excited-state (ES) [1-2]. In this contribution we consider such two lasing state quantum dot laser with optical feedback and we bring new light on the bifurcations leading the system to switch from GS emission to ES or even two-state lasing. Based on the Model described in Viktorov et al. [2], which consider separately electrons and holes dynamics for both emission processes, we use direct numerical integration along with an analytical approach to describe the underlying mechanisms of switching. We identify multiple steady-states and periodic solutions with either GS, ES or two-state emission. We also give unprecedented detail about the impact of the escape coefficient on the laser behavior. Especially we highlight the impact of these coefficients on the antiphase LFF dynamics which appear at high feedback level and reported in [3]. [1] Markus et al., ?Simultaneous two-state lasing in quantum dot lasers?, Appt. Phys. Lett. 82, 1818 (2003). [2] Viktorov et al., ?Electron-hole asymmetry and two-state lasing in quantum dot lasers?, Appl. Phys. Lett. 87, 053113 (2005). [3] Viktorov et al. ?Low-frequency fluctuations in two-state quantum dot lasers?, Opt. Lett. 31, 2303 (2006).