Non-linear optical susceptibilities, Raman efficiencies and electrooptic tensors from first-principles density functional perturbation theory

摘要

The non-linear response of infinite periodic solids to homogenous electricfields and collective atomic displacements is discussed in the framework ofdensity functional perturbation theory. The approach is based on the 2n + 1theorem applied to an electric-field-dependent energy functional. We report theexpressions for the calculation of the non-linear optical susceptibilities,Raman scattering efficiencies and electrooptic coefficients. Differentformulations of third-order energy derivatives are examined and theirconvergence with respect to the k-point sampling is discussed. We apply ourmethod to a few simple cases and compare our results to those obtained withdistinct techniques. Finally, we discuss the effect of a scissors correction onthe EO coefficients and non-linear optical susceptibilities.