Sideband locking of a single-section semiconductor distributed-feedback laser in an optical phase-lock loop

Abstract

The bandwidth and performance of optical phase-lock loops (OPLLs) using single-section semiconductor la- sers (SCLs) are severely limited by the nonuniform frequency modulation response of the lasers. It is dem- onstrated that this restriction is eliminated by the sideband locking of a single-section distributed-feedback SCL to a master laser in a heterodyne OPLL, thus enabling a delay-limited loop bandwidth. The lineshape of the phase-locked SCL output is characterized using a delayed self-heterodyne measurement.