▎ 摘　　要

A continuous wave (CW) Tm: YAP laser resonantly pumped Ho: YLF laser in CW mode and passive Q-switched (PQS) mode with multilayer graphene as a saturable absorber is reported. A comparison analysis of laser performances with two different output couplers is carried out. In PQS mode, an maximum average output power of 2.26 W is obtained, corresponding to a slope efficiency of 20.7%. The minimum pulse width observed is 651.9 ns with a center wavelength of 2057.16 nm with a 300-mm radius curvature and 50% transmission output coupler. Meanwhile, the maximum pulse repetition frequency of 59.2 kHz is obtained. The beam quality factor of M-2 was 1.2, which is the near diffraction limit. The results show that multilayer graphene can be used as a saturable absorber in a Ho: YLF laser around a 2-mu m wavelength. (C) 2015 Society of Photo-Optical Instrumentation Engineers (SPIE)