Flash-lamp-pumped Ho:YAG (2090-nm) and Tm:YAG (2017-nm) lasers were, for the first time to our knowledge, passively <i>Q</i> switched by use of a Cr<sup>2+</sup>:ZnSe saturable absorber. A <i>Q</i>-switched Ho laser with 1.3-mJ pulse energy and ~90-ns pulse duration and a <i>Q</i>-switched Tm laser with ~3.2-mJ pulse energy and 90-ns pulse duration were demonstrated. Compared with the free-running output energies at the <i>Q</i>-switching threshold pump levels, the <i>Q</i>-switching efficiencies were approximately 5% for the Ho:YAG laser and 16% for the Tm:YAG laser.
© 2001 Optical Society of America
Tzong-Yow Tsai and Milton Birnbaum, "Q-Switched 2-μm Lasers by use of a Cr2+:ZnSe Saturable Absorber," Appl. Opt. 40, 6633-6637 (2001)