Optical feedback phenomena in semiconductor lasers

Influence of Losses on the Laser Voltage Drop of the Active Section

“…Furthermore, we extend the discussion of the loss dependent voltage shapes to a laser with integrated optical feedback [8,11,12] which can be understood as a second cavity after the laser cavity. In the optical feedback interferometry [13], it is common to use the voltage as a monitor signal.…”

ICL-Based OF-CEAS: A Sensitive Tool for Analytical Chemistry

“…The term optical feedback describes the phenomenon whereby light entering a semiconductor laser facet perturbs the free-running condition of the laser. , The effect has been studied extensively in diode lasers, with a theoretical description of feedback-coupled laser behavior developed by Lang and Kobayashi in 1980 . It was later exploited by Morville et al in their development of OF-CEAS for gas sensing, in which the source of feedback is light returning from a (V-shaped) high finesse optical cavity.…”

Measuring the sensitivity to optical feedback of single-frequency high-power laser diodes

“…While external cavity diode lasers, obtained with high optical feedback power ratios, have been studied extensively [6,7], the opposite is true for low levels of feedback, which are sometimes known as parasitic reflections. The majority of the work at low feedback power ratios was done during the early telecom years and has revolved around avoiding a state known as coherence collapse for distributed feedback (DFB) lasers often caused by reflections from fiber couplings [8,9]. However, the first effects of the feedback can be seen at feedback levels, which are two or three orders of magnitude lower than the levels required for coherence collapse.…”