Passively Q-switched Cr:LiCAF laser with a saturable Bragg reflector

Abstract

We present a low-cost multimode diode pumped passively Q-switched Cr:LiCAF laser operating near 800 nm. AlGaAs-based saturable Bragg reflectors (SBRs) were used for passive Q-switching. The system is experimentally characterized in detail using four different output couplers and two SBRs with different modulation depths. Pulse widths in the 1.5–4 µs range at repetition rates between 18 and 40 kHz were achieved with average powers up to 125 mW. The experimentally obtained results are compared with basic Q-switching theory and further performance improvement in terms of pulse length shortening and peak power scaling is elaborated.