S. Mohamed
S. Jamal
M. Zafer
A. Sh. M. Yassin

High quality GGG:Cr,Ca crystal for passive Q-switching Nd:garnet lasers has been grown by the Czochralski method. Thermal treatment of GGG crystals co-doped with Cr۴+ and Ca۲+ at different temperatures is investigated. The absorption spectra were resolved into different peaks, of modified Gaussian line-shape. Transition from octahedral sites to tetrahedral ones is thermally activated. An optimal temperature interval for this transition was found to be ۱۲۰۰-۱۳۰۰ ˚C. The investigated samples were used as saturable absorbers in flash-lamp pumped Nd:YAG laser, and a pulse width of about ۱۶ nsec was obtained

Cr, Ca:GGG, Czochralski method, Passive Q-switch, Saturable absorber.