Hybrid-Cavity Semiconductor Lasers for Single Mode Operation And Optical Signal Processing

Hybrid-cavity of a Fabry-Pérot (FP) cavity and a microcavity with the microcavity as a wavelength selective reflector are reported for realizing single mode semiconductor lasers. Mode coupling between a microcavity mode and a FP mode results in mode Q factor enhancement and stable single mode operation. Furthermore, optical bistability are realized in the hybrid lasers as the unbiased microcavity working as a saturable absorption. Two bistability regions are realized for the hybrid lasers around threshold current and above threshold with mode competition, and all-optical flip-flop is demonstrated.