We present a new first-principle theory for the calculation of the macroscopic second-order susceptibility chi^(2), based on the Time-Dependent Density-Functional Theory approach. Our method allows to include straightforwardly the many-body effects. We apply the theory to the computation of the Second-Harmonic Generation spectroscopy, showing a very good agreement with experiment for cubic semiconductor GaAs.
@article{arxiv.1001.2472,
title = {Second-Order Nonlinear Optics from First Principles},
author = {Eleonora Luppi and Hannes Hübener and Valérie Véniard},
journal= {arXiv preprint arXiv:1001.2472},
year = {2010}
}