Hybrid gain semi-open cavity structure 2 micron optical fiber random laser

The invention discloses a hybrid gain semi-open cavity structure 2 micron optical fiber random laser which comprises a pump light source, a wavelength division multiplexer, a phosphorus-doped optical fiber and a thulium-doped optical fiber. A 1566nm laser simultaneously pumps a passive phosphorus-doped optical fiber and an active thulium-doped optical fiber, and the characteristic that a phosphorus pentoxide Raman gain peak (1320cm ) of the phosphorus-doped optical fiber coincides with a thulium-doped optical fiber gain peak is fully utilized. A stimulated Raman scattering gain and an active optical fiber gain are obtained in a 2-micron wave band, a 2-micron wave band optical fiber random laser is generated in the distributed Rayleigh scattering semi-open cavity structure, the problem of a large loss of 2-micron wave band optical signals in long-distance passive optical fiber transmission is solved, and the optical fiber random laser in the semi-open cavity structure is obtained. The laser has the charac