Landau levels and magnetopolaron effect in dilute GaAs:N

TL;DR

This paper investigates how nitrogen doping in GaAs affects its energy spectrum under magnetic fields, revealing unique Landau levels and magnetopolaron effects through an extended theoretical model.

Contribution

It extends the Band Anticrossing Model to include magnetic fields and electron-phonon interactions for analyzing GaAs:N's energy spectrum.

Findings

Nitrogen impurities significantly alter Landau levels in GaAs.

Polaron effects lower the cyclotron resonance energy.

Magneto-absorption spectra show asymmetric peaks near cyclotron energy.

Abstract

The magnetic-field dependence of the energy spectrum of GaAs doped with nitrogen impurities is investigated. Our theoretical model is based on the phenomenological Band Anticrossing Model (BAC) which we extended in order to include magnetic field and electron - phonon interaction. Due to the highly localized nature of the nitrogen state, we find that the energy levels are very different from those of pure GaAs. The polaron correction results in a lower cyclotron resonance energy as compared to pure GaAs. The magneto-absorption spectrum exhibits series of asymmetric peaks close to the cyclotron energy.