A Coherent Fiber for an Airborne Heterodyne Sensor

摘要

Three approaches have been chosen for the fabrication of a 10.6 micrometers coherent fiber. The first approach involves cladding our thallium halide fibers either during extrusion or in a separate post-extrusion process. The second approach relies on the successful development of a new 10.6 micrometer transparent glass, ZnCl2. The most speculative approach, derived from planar technology, requires that a cladding stripe be deposited on a ribbon of KRS-5 or other thallium halide. During the first six months of the program we worked on the first two approaches. We attempted to coextrude single-mode fiber from a composite clad-core billet. Unfortunately, the clad-core interface of the extruded fiber was very irregular after every coextrusion attempted. We thus are abandoning this approach. The ZnCl2 glass remains unstable (devitrifies) on exposure to atmospheric moisture. We are continuing our studies to stabilize the glass by adding various dopants. (Author)