IR laser power transmission through silver halide crystals and polycrystalline fibers
- Tel-Aviv Univ. (Israel); and others
Laser-induced breakdown (LIB) thresholds in AgC{sub x},Br{sub 1-x} crystals and fibers were studied under CO{sub 2} laser pulsed and CW excitation. The value of LIB threshold P{sub c} of the bulk crystals is about 7.2{center_dot}10{sup 8} W/cm{sup 2} for AgCl and 4{center_dot}10{sup 9} W/cm{sup 2} for AgBr under 60 ns TEA laser excitation. The LIB threshold in fibers is much smaller; about 2{center_dot}10{sup 8} W/cm{sup 2}. The absorption of the crystals at 10.6 {mu}m changes from 8{center_dot}10{sup -5} cm{sup -1} for AgCl to 2{center_dot}10{sup -5 }cm{sup -1} for AgBr; for fibers with the same composition absorption is much greater (3{center_dot}10{sup -4 }cm{sup -1} for AgCl; 2{center_dot}10{sup -4} cm{sup -1} for AgBr). The dependence of the LIB and IR absorption on composition, and mechanical and temperature treatments suggests that the LIB in silver halide crystals and fibers is due to the avalanche electrons in a high electric field. The initial free electrons for this process are supplied by ionization of the cation vacancy - charged dislocation complexes. The relatively lower optical stability of the fibers is due to the increased concentration of defects formed in the hot extrusion of the crystal. A simple thermal annealing method for reduction of the IR absorption is proposed.
- Research Organization:
- International Society for Optical Engineering, Washington, DC (United States)
- OSTI ID:
- 552300
- Report Number(s):
- CONF-961070-Vol.2966; TRN: 98:009107
- Resource Relation:
- Conference: 28. annual symposium on optical materials for high power lasers - Boulder damage symposium, Boulder, CO (United States), 7-9 Oct 1996; Other Information: PBD: [1997]; Related Information: Is Part Of Laser-induced damage in optical materials: 1996. Twenty-eighth annual Boulder damage symposium, proceedings; Bennett, H.E.; Guenther, A.H.; Kozlowski, M.R.; Newnam, B.E.; Soileau, M.J. [eds.]; PB: 686 p.
- Country of Publication:
- United States
- Language:
- English
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