In this work, we first analyse the behaviour of semiconductor laser in the presence of weak-to-moderate feedback from a single (lumped) and double external cavity setting. Analysis of laser diode in dynamic double cavity configuration shows that the dynamic double cavity does not disturb the stability of the laser device, but it introduces a considerable shift in the emission frequency that is directly related to the feedback strength and the relative phase difference between the phase of the two mirrors, and the phase of electric field inside the laser diode. Conditions for maximum and minimum impact of the laser emission wavelength have been derived. Addressing the issue of distributed optical feedback, optical feedback produced by more than two external mirrors has been also studied. To this aim we have first generalized the Lang and Kobayashi deterministic rate equations model to arbitrary number of external reflectors and provide the corresponding steady-state solution, which is done for the first time. To the best of our knowledge, this kind of study is carried out for the first time.
Read full abstract