设计了以石墨烯作为可饱和吸收体的被动调Q掺钕钇铝石榴石晶体(Nd:YAG)微片激光器。该激光器采用三明治结构，附有石墨烯薄层的YAG晶体紧密压贴于工作物质Nd:YAG晶体上，晶体端面镀膜作为端面镜构成平行平面谐振腔。采用光纤耦合输出激光二极管端面抽运技术，利用石墨烯的可饱和吸收作用，在注入功率为1.17 W时实现微片激光器的调Q运转，获得波长1064.6 nm，重复频率300~807 kHz可调，最小脉冲宽度75 ns的激光输出。激光器最大输出功率38.4 mW，最大单脉冲能量54.7 nJ。

A design passively Q-switched Nd:YAG microchip laser based on graphene saturable absorber is presented. A thin layer of graphene is sandwiched between the Nd:YAG crystal and YAG crystal closely, and dichroic coatings on crystals is used as reflective mirrors for the plane parallel resonator. The Nd:YAG crystal is end pumped by a fiber-coupled laser diode via a lens imaging system. Employing graphene as saturable absorber, Q-switched Nd:YAG microchip laser is realized at the pump power threshold of 1.17 W with laser central wavelength of 1064.6 nm. The minimum pulse duration is 75 ns at 488 kHz and the repetition rate is tunable from 300 to 807 kHz with the increase of the pump power. The maximum output power and highest pulse energy of the laser measured are 38.4 mW and 54.7 nJ respectively.