Optical properties of mixed silver halide crystals and fibers

Abstract

The dependence of the bulk (βb) and surface (βs) absorption coefficients of AgClxBr1−x crystals and of polycrystalline fibers at 10.6 μm on the composition (x) of the material were investigated. The bulk coefficient βb for AgBr was about 0.5×10−4 cm−1 and increased gradually with increasing molar concentration x of the Cl− ions up to 2.5×10−4 for pure AgCl crystals. Luminescence properties of these crystals as well as effects of thermal treatments on the absorption, luminescence, and conductivity were also investigated. A correlation was found between the effects of these treatments on the infrared (IR) absorption, the luminescence, and conductivity of the various samples. Experimental results indicate that the absorption of the silver halide crystals at 10.6 μm is mainly due to cation vacancies bound to dislocations. The absorption of the fibers was found to be greater than that of the crystals of the same composition. This is apparently due to defects induced by the heating under pressure, applied during the production of the fibers by extrusion, and the subsequent fast quenching to room temperature. A simple method for reduction of the IR absorption is proposed.

Middle-infrared luminescence of Nd ions in silver halide crystals

“…The properties of silver halide crystals and of fibers extruded from these crystals have been under active study by the Applied Physics Group at Tel-Aviv University. Both crystals and fibers are highly transparent in the near and mid-IR ranges, they are non-toxic and non-hygroscopic, and the fibers are flexible and have desirable mechanical properties [11,12]. The silver-halide crystals may, therefore, serve as practical hosts for mid-IR solid-state lasers.…”

Phase diagram and electrical conductivity of the AgBr–NdBr3 binary system

“…The luminescence of AgBr, AgCl, and AgCl x Br 1−x crystals and fibers doped with several lanthanide Ln 3+ ions was investigated in the middle-infrared range [2][3][4][5][6][7][8]. These materials are highly transparent in the near and mid-IR ranges and have desirable mechanical and optical properties.…”

“…The high ionic conductivity of some solid silver halide phases makes them good candidates for a number of technological applications such as solid electrolytes in electrochemical power systems [1] or solid-state lasers that operate in the middle-infrared spectral range [2][3][4][5][6][7][8]. The luminescence of AgBr, AgCl, and AgCl x Br 1−x crystals and fibers doped with several lanthanide Ln 3+ ions was investigated in the middle-infrared range [2][3][4][5][6][7][8].…”

Rare earth doped silver halide crystals: a new candidate for mid-IR solid lid state lasers & fiber lasers and amplifiers

“…Silver halide crystals of the form AgCl x Br 1-x (0<x<1) seem to be attractive candidates as host materials for mid-IR fiber lasers and amplifiers, as well as for solid state bulk devices. They are highly transparent over a broad spectral range (up to 30µm), they have an extremely low optical phonon energies (80 cm -1 in AgBr and 103 cm -1 in AgCl), and they can be extruded to form optical fibers [3].…”