Comprehensive Investigations on 1053 nm Random Distributed Feedback Fiber Laser

We design a 1053 nm Yb 3+ -doped random fiber laser (YRFL) based on the combination of Yb 3+ -doped fiber (YDF) and single mode fiber (SMF), in which the YDF provides active gain, while SMF offers random distributed feedback. The numerical model is established based on the rate equation of Yb 3+ -doped laser, and it is modified and developed to calculate the power performance of YRFL. The numerical results show that the YDF's length and the pumping scheme could influence the laser power performance. Then, the forward and backward pumped YRFL both with 9.5 m YDF and 2 km SMF are experimentally demonstrated whose threshold powers are 1 and 1.1 W, respectively. The obtained optical slope efficiencies are 45.2% and 40.9% for these two cases. The experimental results agree with the calculated results well. This work gives a general study on active gain based random fiber lasers, which can enrich the operation wavelength range of random fiber laser and may broaden its application fields to high energy large-scale laser facilities.