Cr~(2+): ZnSe Crystal Based High Power Passively Q-switched Tm-doped Fiber Laser

摘要

We presented a passively Q-switched Tm~(3+)-doped fiber laser using Cr~(2+) : ZnSe crystal as saturable absorber. By employing a crystal with 70% initial transmission, stable Qswitched pulses with a repetition rate of 150.7 kHz and pulse duration of 160 ns were achieved at the maximum pump power of 7.13 W. The obtained maximum output power of 1.32 W was also the reported highest level from the Cr~(2+) : ZnSe crystal based passively Q-switched Tm~(3+)-doped fiber lasers. Moreover, an 80% initial transmission Cr~(2+) : ZnSe crystal was also employed to compare. Stable Q-switched pulses with maximum output power of 0.96 W at a repetition rate of 138.1 kHz and pulse duration of 352 ns were obtained at the launched pump power of 4.19W. Further increasing of the pump power will lead to the unstable Q-switching regime.