“…[14] It is to be noted that, although several high-power Raman fiber lasers with fixed wavelengths have been reported with hundred-watt level output power, [15][16][17][18][19] the output power of tunable Raman fiber lasers is still rather low, i.e., no more than the 10 W level. Besides high output power, linearly polarized operation is also an important demand in many applications owing to high efficiency, [20,21] such as harmonic generation, [22,23] parametric conversion, [24,25] coherent detection, coherent beam combination, [26,27] spectral beam combination, [28,29] and supercontinuum generation. [30,31] Nevertheless, to the best of our knowledge, there have been no reports on high power linearly-polarized tunable Raman fiber lasers yet.…”