Tunable Photonic Oscillators Using Optically Injected Quantum-Dash Diode Lasers

An analytical approximation is described and experimentally verified for predicting the resonance frequency of an optically injected quantum-dash Fabry-Pe¿rot laser in the period-one (P1) state. Due to the large spontaneous and nonlinear carrier relaxation rates measured in nanostructure lasers, the P1 resonance frequency is modified appreciably. The function presented accounts for these effects, and it also identifies the role of the linewidth enhancement factor of the optically injected slave laser. The resulting equation is shown to improve the P1 resonance frequency calculation when compared to previous models. Calculating the P1 resonance frequency is critical in using optically injected lasers as a building block for tunable photonic oscillators.