Nonlinear Dynamics in Semiconductor Lasers 2023 - Abstract
Seegert, Kristian
Integrating a passive dispersive reflector (PDR) in a semiconductor laser will influence the laser dynamics and properties in several ways. This leads to a variety of possible applications, including linewidth narrowing, enhancement of the modulation response, generation of short pulses dispersive self-Q-switching, and multi-color emission. Examples of lasers with integrated PDRs include lasers based on Fano resonances, multi-section distributed-feedback lasers, lasers coupled to microring resonators, and external feedback lasers. In this work we consider an arbitrary PDR, which is characterized by a frequency dependent effective reflectivity, and study the effects on relaxation oscillations, photon-photon resonances, and more. As a key result, we derive a modified characteristic equation for the linearized system that explicitly takes into account the frequency dependent mirror. Further, we derive approximate expressions for the relaxation oscillation frequency and damping rate that depend on the local shape of the reflectivity. As such, the model can be used as a design guideline for the spectral response of the PDR. Finally, we apply the model to study two particular examples of microscopic Fano lasers. In one example, we observe self-pulsing which is interpreted as dispersive self-Q-switching. In another example, an EIT resonance in a photonic molecule is used to engineer the dispersion to support stable, tunable two-color lasing, which dynamically corresponds to sinusoidal beating-type oscillations. The beating-type oscillations can be associated with the excitation of a photon-photon resonance due to the Bogatov effect.