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

Vidar Gudmundsson·Chi-Shung Tang·Andrei Manolescu
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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.

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Vidar Gudmundsson, Chi-Shung Tang, Andrei Manolescu. 2003-04-25. Impurity and spin effects on the magneto-spectroscopy of a THz-modulated nanostructure. https://doi.org/10.1103/physrevb.68.165343

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