Thermally induced damage studies with shaped light

Abstract

We outline an all-optical and noncontact approach for controlled laser heating and measurement of the resultant temperature distribution at the surface of a material, respectively. We show how the boundary conditions of the heating problem may be controlled optically through shaping of the pump light and use the examples of both Gaussian and flat-top beams. These two beams, together with appropriate nonoptical boundary control, allow for the laser-induced thermal study of materials with and without thermal stress. We illustrate the technique on an industrial diamond sample where a gradient and uniform temperature profile on the surface of the diamond was successfully created and measured. We use the technique to study the thermally induced degradation of industrial diamond in a controlled manner.