ABSTRACT
This chapter compiles physical, structural, optical, thermal, and mechanical properties of a variety of laser-host crystals. It serves as a supplement to an earlier compilation of these properties; most of the materials covered are either new or have been the subject of renewed interest during the past several years. Hardness values for many crystals have been measured using either static indentation or scratch tests. Knoop hardness values are determined by measuring the area of the unrecovered indentation made by a rhombic-based pyramidal diamond probe under a given load. Mohs hardness values are indicative of the relative ability of one material to scratch another. Ten standard materials are defined for this purpose, with talc being the softest (Mohs hardness 1) and diamond the hardest (Mohs hardness 10). The wide variance between theory and experiment is primarily caused by the sensitive dependence of the materials’ strength on the subsurface damage resulting from grinding and polishing.
