Impurity and spin effects on the magneto-spectroscopy of a THz-modulated nanostructure

TL;DR

This paper introduces a grid-free DFT model to study the time evolution of electronic states in semiconductor nanostructures, focusing on impurity and spin effects under THz excitation.

Contribution

The paper develops a novel grid-free DFT approach for dynamic analysis of nanostructures, enabling investigation of impurity and spin effects in magneto-spectroscopy under THz radiation.

Findings

Impurity binding energy decreases with stronger THz excitation.

Collective spin-oscillations emerge at finite magnetic fields and can be suppressed by increased excitation.

The model captures both linear and nonlinear responses of the system.

Abstract

We present a grid-free DFT model appropriate to explore the time evolution of electronic states in a semiconductor nanostructure. The model can be used to investigate both the linear and the nonlinear response of the system to an external short-time perturbation in the THz regime. We use the model to study the effects of impurities on the magneto-spectroscopy of a two-dimensional electron gas in a nanostructure excited by an intense THz radiation. We do observe a reduction in the binding energy of the impurity with increasing excitation strength, and at a finite magnetic field we find a slow onset of collective spin-oscillations that can be made to vanish with a stronger excitation.