Mode locked and Q-switched Cr:ZnSe laser using a Semiconductor Saturable Absorbing Mirror (SESAM)

Abstract

A passively mode-locked cw Cr:ZnSe laser operating near 2.5 μm generated 400 mW of output power with 11 psec pulse duration and 100 MHz repetition rate using a Semiconductor Saturable Absorbing Mirror (SESAM). Adjusting the cavity to be significantly shorter and have a weaker focus on the SESAM, passive Q-switched operation could also be obtained with the same SESAM. Q-switched operation produced 50 nsec pulses with a 1 MHZ repetition rate, and peak powers of 10 W. In both mode-locked and Q-switched operation, the laser was pumped with 2.4W from a Tm:YALO laser.