▎ 摘　　要

A passively Q-switched Ho:LuAG solid-state laser using a graphene saturable absorber pumped by a continuous-wave diode-pumped Tm:YLF laser was first reported in this letter. Single layer graphene grown by chemical vapor deposition and transferred onto a thin quartz plate was fabricated as the SA. For the continuous-wave mode, a maximum output power of 0.87W at 2100.7 nm was obtained under the output coupler T=10%, corresponding to the slope efficiency of 30.8% and the optical conversion efficiency of 18.9%. For the passively Q-switched mode, a stable PQS Ho:LuAG laser under the highest incident pump power of 4.3 W was obtained, corresponding to the maximum average output power, the maximum repetition frequency and the minimum pulse width being 037W, 48.8 kHz and 752.2 ns, respectively. Our results illustrate that graphene can be used well as a saturable absorber in a Ho-doped solid-state laser at 2 mu m wavelength. (C) 2015 Elsevier GmbH. All rights reserved.