Novel measurement method of linewidth enhancement factor in semiconductor lasers by optical self-locking

Abstract

We propose a simple, accurate and novel method to measure the value of the linewidth enhancement factor in semiconductor lasers. It utilises the asymmetry of the frequency locking range of a semiconductor laser with the optical feedback from the external CFP cavity. The measured value for a 0.8μm CSP-type AlGaAs laser was 3.07±0.26, which showed good agreement with those measured by other conventional methods.