title: Optical triggering of a Q-switched Nd:YAG laser via transverse bleaching of a Cr:YAG saturable absorber.
abstract: Optical triggering via direct bleaching of a Cr:YAG saturable absorber was applied to a monolithic Nd:YAG/Cr:YAG laser crystal. The method uses a single laser diode bar to bleach a thin sheet within the saturable absorber from a direction orthogonal to the lasing axis. By placing the Q-switch at the time corresponding to the steepest slope (dT/dt) for change in transmission during bleaching, the pulse-to-pulse timing jitter showed a 13.2x reduction in standard deviation, from 132 ns for free-running operation to 10 ns with optical triggering. We measured that a fluence of 60 kW/cm(2) was sufficient to enable optical triggering, where a diode appropriately sized for the length of the Cr:YAG (approximately 3 mm) would then require only approximately 150 W of optical power over a 1-2 micros duration to enable effective jitter reduction. Additionally, we measured an increase in optical-to-optical efficiency with optical triggering, where the efficiency improved from 12% to 13.5%.
authors.affiliation: U.S. Army Research, Development and Engineering Command (RDECOM), Communications-ElectronicsResearch, Development, and Engineering Center (CERDEC), Night Vision and Electronic Sensors Directorate, Fort Belvoir, Virginia 22060, USA. info@nvl.army.mil
authors.forename: Brian
authors.initials: B
authors.lastname: Cole
authors.forename: Jonathan
authors.initials: J
authors.lastname: Lei
authors.forename: Tom
authors.initials: T
authors.lastname: DiLazaro
authors.forename: Bradley
authors.initials: B
authors.lastname: Schilling
authors.forename: Lew
authors.initials: L
authors.lastname: Goldberg