Active Q-switching operation of a Tm:SrF2 single crystal fiber laser near 2 µm

Abstract

Single crystal fiber (SCF) lasers have attracted extensive attention recently. In this paper, Tm:SrF2 SCF was successfully grown by the temperature gradient method. With a compact resonator, the acousto-optically Q-switched properties of a diode-pumped Tm:SrF2 SCF laser was investigated first. At the repetition rate of 500 Hz, a highest pulse energy of 1.32 mJ and a narrowest pulse width of 51 ns were acquired with the absorbed pump power of 2.60 W, resulting in the peak power of 25.85 kW. These results indicate that Tm:SrF2 SCF is a promising laser gain material for generating ∼2 µm region pulsed lasers.