Magneto-Optical Properties of Electron Gas in a Chain of Planar Quantum Rings: Effect of Screening on the Signature of Quantum Phase Interference

Abstract

The equilibrium properties and interminiband transitions for Hartree-interacting 2D electron gas in a 1D chain of planar quantum rings subjected to a transverse homogeneous magnetic field are examined. The proposed analytical models for the modulation potential and the basis wave-function reflect the symmetry and the topology of the system allowing to get high accuracy results. The calculated dependencies of the electronic band structure versus magnetic field show two detached minibands in the region of low energies, while higher minibands manifest crossings and anticrossings. The existence of highly degenerate energy levels (miniband nodes) for certain values of magnetic field is revealed. The miniband nodes are preserved when taking into account the Coulomb interaction of the electrons. The interaction causes both an upward shift and broadening of minibands, while also shifting the nodes to higher magnetic fields. The miniband nodes have their signature in the magnetization of the electron gas and in the interminiband transitions. The number of electrons per a unite cell of the system has a strong impact on the current density distribution, magnetization and the oscillator strength. The obtained results open new opportunities for a flexible manipulation of magneto-optical properties of future devices operating in far-infrared and THz regimes.