Experimental study on linewidth compression based on Rayleigh backscattering in 1064Â nm fiber laser

Attributed to the unique energy level structure of the Yb 3+, it is arduous to effectively compress the linewidth of Ytterbium-doped fiber (YDF) laser by conventional methods. Herein, we investigated Rayleigh backscattering (RBS) characteristics in single mode fiber-1060-XP (SMF-1060-XP) and the linewidth compression efficacy of RBS in 1064 nm laser system. A single longitudinal mode (SLM) fiber laser operating at 1064 nm has been obtained, and the 3 dB linewidth can be compressed from 8.01 kHz to 1.35 kHz thereby yielding a side mode suppression ratio as high as ∼50 dB provided the pump power is set to 390 mW. The theoretical prediction suggests the feasibility to actualize a linewidth of hundreds of Hertz provided the experimental setup is further optimized. The investigation of our work has a potential application in the study of linewidth compression of short cavity lasers or DFB lasers operating at a 1064 nm wavelength.