Thallium halide fiber waveguides for middle infrared range

The extrusion method was used in the fabrication of TlCl, TlBr, KRS-6, and KRS-5 fiber waveguides in which the minimum optical losses were ~3×10^–3 cm^–1 at wavelengths of 5–6 and 10.6 μ. Fibers 1 mm in diameter were not damaged by power densities of ~1 kW/cm². The region of minimum material dispersion in KRS-6 and KRS-5 was found to coincide with the region of minimum optical losses.