2 kW random fiber laser based on hybrid Yb-Raman gain [Invited]

High-power operation is one of the most important research topics surrounding random fiber lasers (RDFLs). Here we optimized cavity structure and proposed a new scheme based on hybrid gain to address issue high-power backward light in traditional kilowatt-level RDFLs. Consequently, record power 1972 W was achieved while maximum leaked only reached 0.12 W. The conversion efficiency relative laser diode pump 68.4%, highest spectral purity lasing 98.1%. This work may provide reference for RDFLs, Raman lasers, long-wavelength Yb-doped lasers.