Author:
Gao Ruixiang,Fang Qiang,Xu Yang,Gao Song,Jiang Peiheng,Fu Shijie,Sheng Quan,Shi Wei
Abstract
Abstract
Based on the self-injection locking technique, we demonstrate a low-noise and narrow linewidth of 2 μm single-frequency distributed Bragg reflection fiber laser with an optical self-injection feedback loop (OSIFL). The OSIFL consists of a piece of delay fiber and two polarization-maintaining optical couplers, which can effectively narrow down the linewidth and suppress the relative intensity noise (RIN) of the laser. It was observed that the laser linewidth was narrowed down from the initial 6.5 kHz to 1.6 kHz while the laser relaxation oscillation peak was reduced from -100.3 dB/Hz to -113.5 dB/Hz. Experimental results demonstrate that by extending the photon lifetime we can effectively narrow down the linewidth and significantly reduce the RIN of the laser. This research is of great significance for promoting the development and application of 2 μm single-frequency lasers.