title: Saturation of 640-nm absorption in Cr⁴⁺:YAG for an InGaN laser diode pumped passively Q-switched Pr³⁺:YLF laser.
abstract: We measure the absorption recovery time, the ground- and excited-state absorption cross sections of a Cr4+:YAG crystal at 640 nm for the first time. A pump-probe measurement reveals the existence of two recovery times of 26 ns and 5.6 μs. By a Z-scan experiment, the ground- and excited-state absorption cross sections are estimated to be 1.70 - 1.75 × 10(-17) and 0.95 - 1.00 × 10(-17)cm2, respectively. The adequacy of the proposed model and the accuracy of the estimated parameters of the saturable absorber are verified by reproducing the experimentally obtained performance of a passively Q-switched Pr3+:YLF laser with the Cr4+:YAG saturable absorber from rate equation analysis.
authors.forename: Hiroki
authors.initials: H
authors.lastname: Tanaka
authors.forename: Ryosuke
authors.initials: R
authors.lastname: Kariyama
authors.forename: Kodai
authors.initials: K
authors.lastname: Iijima
authors.forename: Kenichi
authors.initials: K
authors.lastname: Hirosawa
authors.forename: Fumihiko
authors.initials: F
authors.lastname: Kannari