Ion exchange for optical waveguides in ZnSe crystals: regularities and specific features

A new method has been applied to form CduZn1-uSe waveguides -- ion exchange in the melts of salts. The regularities and specific features of ion exchange processes Cd2+ yields Zn2+ in ZnSe powder and single crystal plates have been studied. CduZn1-uSe solid solution obeys the model of regular solution. Temperature dependencies of equilibrium constant and interaction energy of strained and unstrained CduZn1-uSe solid solutions have been defined. We proposed the model taking into account the role of lattice misfit-induced stresses and dislocations in the ion exchange equilibrium. The depth profiles of elements and the refractive-index profiles in the ion exchanged Cd:ZnSE waveguides were analyzed and temperature dependencies of the self-diffusion coefficients of Cd2+ and Zn2+ ions were determined.