Graphene-based passive Q-switching of a Dy3+,Tb3+:LuLiF4 yellow laser

We report solid-state continuous-wave (cw) and Q-switched lasers directly emitting in the yellow spectral region, which include a Dy3+,Tb3+:LuLiF4 crystal as the laser material and a single-emitter blue laser diode (LD) as the pump source. Without resorting to any nonlinear conversion process, a maximum output power of 351 mW is obtained for the cw yellow laser with a slope efficiency of 15% at the wavelength of 573.9 nm. For generating the Q-switched yellow laser, a monolayer graphene is used as the saturable absorber. The maximum average output power of the Q-switched yellow laser is determined to be 85 mW. The shortest pulse width is obtained as approximately 596 ns, which corresponds to a repetition rate of 78 kHz. The calculated pulse energy and peak power are nearly 1.1 μJ and 1.8 W, respectively. Overall, the proposed approach exhibits immense potential for fabricating compact and economical solid-state cw and Q-switched yellow lasers.