Abstract

The second-harmonic-generation coefficients d=½χ⁽²⁾ of four III-V semiconductors and their derivatives with respect to the lattice constant a are calculated in the static limit. We use the local density approximation (LDA) implemented in a plane wave basis with first principles pseudopotentials. We correct for the self-energy of the band gaps by a scissors operator, for example, we add a term to the LDA Hamiltonian to shift the conduction bands upward (by just under 1 eV) to match the values in the literature for the calculated GW quasiparticle excitation energies.^1-4 We calculate linear optical properties in the same model.

© 1991 Optical Society of America