Measurement of the thermal diffusivity of nonlinear anisotropic crystals using optical interferometry

We describe a simple common-path self-referencing interferometric method requiring no auxiliary optical elements which accurately and directly measures the thermal diffusivity of anisotropic crystals in nonsteadystate conditions. We determine the thermal diffusivity of a lithium niobate crystal as a function of temperature ranging from room temperature up to 500 degrees C.