# Macroscopic electron-hole distribution in silicon and cubic silicon carbide

## TL;DR

This paper models the spatial distribution of electron-hole pairs in silicon and cubic silicon carbide under femtosecond laser excitation, revealing how quasi-temperatures vary with depth and band structure.

## Contribution

It introduces a combined computational approach using time-dependent density functional theory and Maxwell's equations to analyze electron-hole distributions in these materials.

## Key findings

- Electron-hole quasi-temperatures decrease exponentially from the surface.
- 3C-SiC shows stepwise temperature decrease due to band structure changes.
- Quasi-temperatures depend on both excitation mechanisms and band structure.

## Abstract

Electron excitations at silicon and 3C-SiC surfaces caused by an intense femtosecond laser pulse can be calculated by solving the time-dependent density functional theory and the Maxwell's equation simultaneously. The energy absorption, carrier density, and electron-hole quasi-temperatures decrease exponentially in 100 nm from the surface. The electron and hole quasi-temperatures have finite values even at large distances from the surface because of a specific photo-absorption channel. Although the quasi-temperature in the silicone shows smooth exponential descrease, 3C-SiC shows stepwise decrease because of the change of concerning bands. The quasi-temperature depends not only on the excitation process, i.e., tunnel and multi-photon absorption, but also on the band structure significantly.