Refractive-index measurements of zinc germanium diphosphide at 300 and 77 K by use of a modified Michelson interferometer

摘要

A method to determine the absolute refractive index of materials available in the shape of flat wafers with parallel sides by using interferometric techniques is presented. With this method, nondestructive, sample-specific measurements can be made. The method is tested by using silicon, germanium and zinc selenide, and measurements for both the ordinary and extraordinary axes of ZnGeP_(2) for temperatures of 300 and 77 K are reported.