CO₂ laser power transmission and laser induced breakdown in AgCl_xBr_1-x crystals, polycrystals, and fibers

Laser-induced breakdown (LIB) thresholds in AgCl_xBr _1-x crystals, polycrystals, and fibers were studied under CO ₂ pulse laser excitation. The limit value of LIB threshold P _c of the bulk crystals is about 4×10⁸ W/cm ² for x=1 and 8×10⁸ W/cm² for x=0 under 100 ns transversely excited atmospheric pressure laser excitation. The LIB threshold in fibers is much smaller; about 2×10⁷ W/cm ². The dependence of the LIB on composition and temperature suggests that the main cause for LIB is electron avalanche combined with multiphonon absorption at 10.6 μm in silver halide crystals.