Abstract
We investigate the characteristics and applications of nonlinear dynamics generated by semiconductor lasers subject to optical feedback. The optical feedback perturbs the carrier and the refractive index in the laser cavity shifting the cavity resonant frequency. Rich dynamics such as chaos (C), quasi-periodic (QP), period-one (P1), regular pulse package (RPP), and low frequency fluctuation (LFF) can be generated. In the first part of this dissertation, we introduce the nonlinear dynamics generated by semiconductor lasers subject to different perturbations and focus on the optical feedback dynamics. Next, we discuss the P1 oscillation and utilize it as the light source in developing a self-mixing dual-frequency laser Doppler velocimeter (SM DF-LDV) capable of the speckle noise reduction and the coherence enhancement. For improving the velocity resolution and replacing the bulky and costly microwave signal generator, in the second part, we compare linewidths and stabilities of the P1 oscillations generated by optical injection (OI) and optical feedback (OF). In addition, quantum dot lasers possessing low relative intensity noise (RIN) and low temperature sensitivity are very different from the quantum well (QW) lasers. They are expected to generate more stable periodic oscillation. In the fourth part, we investigate the dynamical states and their spectral characteristics of the optical feedback multimode quantum dot (QD) semiconductor lasers emitting exclusively on sole ground state and excited state.