High side-mode suppression ratio laser output by single sideband injection locking of semiconductor lasers

Abstract

High side-mode suppression ratio (SMSR) and higher optical power output of frequency converted lightwave is successfully realized by single side band injection locking of distributed feedback laser (DFB). This method is of great potential in the application of fast optical frequency sweep signal generation. Compared to that acquired from direct carrier suppressed single sideband (CS-SSB), the SMSR of the injection locked slave laser by single sideband injection locking is much higher (32.5dB to 12dB at best), and the power of the injection locked slave laser output is 11dB higher (-22dBm to -33.5dBm) than converting directly from CS-SSB. The variation of SMSR and locking bandwidth of the slave laser as optical injection ratio changes is also researched.