Optimizing of the piezo-optic interaction geometry in SrB4O7 crystals

The optimal geometries of the piezo-optic interaction are determined for SrB₄O₇ crystals by the extreme surfaces method. The goal functions of optimization are the change of optical path length and optical path difference, normalized on mechanical stress and crystal thickness, and the parameters of optimization are the spherical angles determining the directions of the light beam propagation and the uniaxial pressure action. It is shown that the maximal changes of optical path length for the orthogonal polarized waves are equal to 2.09 or 1.65 B (1 B = 1 brewster = 10^–12 m²/N) and the maximal change of optical path difference is equal to 2.22 B respectively in transversal geometry of the piezo-optic interaction (for λ =633nm and T =20ºC).