title: 50-mJ, Q-switched, 2.09-microm holmium laser resonantly pumped by a diode-pumped 1.9-microm thulium laser.
abstract: We report >50-mJ Q-switched energy output from a 2.09-microm Ho:YAG oscillator, resonantly pumped at 1.9-microm by a diode-pumped Tm:YLF laser. We demonstrate a Q-switched-to-normal-mode extraction efficiency of 100% at an output energy of 30 mJ and over 64% at the 50-mJ output level. Operating at 50 mJ (60 Hz) of output, a pulse width of 14 ns is achieved from the holmium oscillator, which corresponds to approximately 3.6 MW of peak power. At the 50-mJ output level, a beam-propagation factor M2 approximately 1.2 is achieved.
authors.affiliation: BAE Systems, PO Box 868, Nashua, New Hampshire 03060-0868, USA.
authors.forename: P A
authors.initials: PA
authors.lastname: Budni
authors.forename: C R
authors.initials: CR
authors.lastname: Ibach
authors.forename: S D
authors.initials: SD
authors.lastname: Setzler
authors.forename: E J
authors.initials: EJ
authors.lastname: Gustafson
authors.forename: R T
authors.initials: RT
authors.lastname: Castro
authors.forename: E P
authors.initials: EP
authors.lastname: Chicklis