Passive Q-switching operation and nonlinear spectroscopy of Cr/sup 4+/:CaGd/sub 4/(SiO/sub 4/)/sub 3/O and Cr/sup 4+/:SrGd/sub 4/(SiO/sub 4/)/sub 3/O crystals

Summary form only given. Cr/sup 4+/-doped crystals are known as lasing media for tunable solid-state lasers in the near infrared spectral range as well as useful passive Q-switches for several solid-state lasers. In this report, we study nonlinear optical properties and saturable absorber Q-switching operation of Cr/sup 4+/:SrGd/sub 4/(SiO/sub 4/)/sub 3/O and Cr/sup 4+/:CaGd/sub 4/(SiO/sub 4/)/sub 3/O crystals. Nanosecond intensity-dependent transmission at 1.06 /spl mu/m and 694 nm are presented, from which the absorption cross sections and excited states are estimated.