Аннотация:An Ytterbium-Holmium co-doped all-fiber CW laser is reported. The fiber used in the laser setup has been fabricated through the conventional MCVD process in conjunction with the SD technique and finally drawn using a standard fiberdraw tower. The laser was built in a linear Fabry-Perot configuration in which two fiber Bragg gratings reflecting at 2.05 mu m were used as the cavity couplers. Under 1.06-mu m in-core pumping of the fiber, CW lasing at 2.05 mu m was provided due to energy transfer Yb3+-> Ho3+. The laser demonstrated low threshold (similar to 0.8 W), moderate slope efficiency of lasing (similar to 8.4% when measured vs. pump power launched into the active fiber), and high stability: during 6 hours its output power fluctuated within a 3% range. The laser spectrum width at a 3-dB level using an optical spectrum analyzer with a 37-pm resolution was measured to be similar to 70 pm.