Electrical single mode switching in coupled microcavity

Abstract

Flexible lasing mode regulation is significant for optoelectronic applications, such as on-chip communication and optoelectronic integration. However, reversible and dynamic single mode lasing output is still a challenge. Herein, reversible lasing modes tuning is demonstrated in whispering gallery mode microcavity controlled by bias voltages. Especially in coupled microcavity consisting of two microrods, applied electrical fields cause lasing modes shifting of one microrod, and the optical field coupling process with the other microrod occurs simultaneously to select distinct single mode lasing. Hence, the switchable single mode lasing can be achieved. The mechanisms of Vernier effect, electro-optic effect, and their synergy on lasing mode modulation are analyzed via experimental results and theoretical analysis. Synergistically running the two effects, the high quality factor of the single mode indicates an effective coupling process, providing an effective way for controllable lasers.