Light deflection in gadolinium molybdate ferroelastic crystals

The deflection of a He-Ne light beam by polydomain gadolinium molybdate (GMO) crystals has been studied with respect to incidence angle i on the sample at room temperature. The A and B deflected beams do not cross each other during the i variation, in contrast to results and calculations previously published. The model using the Fresnel equation confirms this result. The model presented is more accurate for numerical calculation than that using the Huygens construction.