High order harmonic generation in semiconductors driven at near- and mid-IR wavelengths

TL;DR

This study investigates high order harmonic generation in silicon and diamond using time-dependent density functional theory, demonstrating the importance of pulse duration and atomic dephasing effects on the spectra.

Contribution

It provides a detailed simulation of HHG in semiconductors at near- and mid-IR wavelengths, including dephasing effects, using advanced first-principles methods.

Findings

Clear HHG spectra depend on pulse duration

Dephasing effects influence harmonic intensities

Results align with previous experimental and theoretical studies

Abstract

We study high order harmonics generation (HHG) in crystalline silicon and diamond subjected to near and mid-infrared laser pulses. We employ time-dependent density functional theory and solve the time-dependent Kohn-Sham equation in the single-cell geometry. We demonstrate that clear and clean HHG spectra can be generated with careful selection of the pulse duration. In addition, we simulate dephasing effects in a large silicon super-cell through displacement of atomic positions prepared by a molecular dynamics simulation. We compare our results with the previous calculations by Floss et al. [arXiv:1705.10707] [Phys. Rev. A 97, 011401(R) (2018)] on Diamond at 800 nm and by Tancogne-Dejean et al. [arXiv:1609.09298] [Phys. Rev. Lett. 118, 087403 (2017)] on Si at 3000 nm.