Many-body effects in the cyclotron resonance of a magnetic dot

TL;DR

This paper investigates how a magnetic ion influences cyclotron resonance in a two-electron quantum dot, revealing many-body effects that alter transition energies and spectral features, deviating from traditional parabolic quantum dot behavior.

Contribution

It demonstrates that the presence and position of a magnetic ion cause significant many-body effects, breaking Kohn's theorem and modifying the CR spectrum in quantum dots.

Findings

CR transition energies are shifted by many-body interactions.

The number of CR lines varies with Coulomb interaction strength.

Magnetic ion position affects crossing and anti-crossing features.

Abstract

Intraband cyclotron resonance (CR) transitions of a two-electron quantum dot containing a single magnetic ion is investigated for different Coulomb interaction strengths and different positions of the magnetic ion. In contrast to the usual parabolic quantum dots where CR is independent of the number of electrons, we found here that due to the presence of the magnetic ion Kohn's theorem no longer holds and CR is different for systems with different number of electrons and different effective electron-electron Coulomb interaction strength. Many-body effects result in \emph{shifts in the transition energies} and \emph{change the number of CR lines}. The position of the magnetic ion inside the quantum dot affects the structure of the CR spectrum by changing the position and the number of crossings and anti-crossings in the transition energies and oscillator strengths.