Random Distributed Feedback Raman Fiber Laser With Short Cavity and Its Temporal Properties

We demonstrate a random distributed feedback Raman fiber laser with relatively short cavity in a half open cavity scheme. A record output power of 4 W in 1173 nm is obtained and the slope efficiency is more than 90%. Second-order Stokes wave at 1237 nm is also achieved with powers in two output ends of 4.1 and 0.8 W, respectively. The linewidth of the Stokes waves are recorded and discussed. We observed self-oscillation at the pump power a little above the second-order Stokes wave generation threshold, and a temporal-spatial-coupled numerical model is proposed. Numerical simulations have good agreement to the experiment results.