Band structure and birefringence of LiRbSO4 crystals

Abstract

Theoretical and experimental investigations of the energy-band structure and optical properties of LiRbSO₄ crystals of the orthorhombic Pnma phase have been performed. The band structure, density of states, and permittivity distribution ε(E) have been calculated within the electron-density functional theory by the pseudopotential method. Spectral dependences of birefringence Δn_і of LiRbSO₄ crystals for different crystallophysical directions have been obtained based on these calculation results. The experimental and theoretical birefringence spectra are found to be in good agreement.