Passively mode-locked diode-pumped Tm,Ho:LiYF4 laser

We report on the first demonstration of a diode-pumped passively mode-locked Tm,Ho:LiYF4 laser. Stable continuous-wave mode-locking is achieved by employing a single-layer graphene as a saturable absorber (SA). For a reflection-type graphene-SA, the laser delivers 5.2 ps pulses at ~2051 nm with an average output power of 40 mW at a repetition rate of 89.86 MHz. With a transmission-type graphene-SA and smaller output coupling, the output power is scaled up to 80 mW while the laser operated in a double-pulse regime.