Optical properties of two interacting electrons in quantum rings: Optical absorption and inelastic light scattering

Two interacting electrons confined in a quantum ring form a Wigner molecule due to the interplay between the Coulomb repulsion and the radial confinement. The states with fixed total spin show a strong correlation between the quantum numbers of the relative angular vibrations and the rotation of the two electrons. On the basis of the energy band structure, which results in the occurrence of a persistent current in the ring, the optical absorption and the differential cross section of resonant inelastic light scattering is calculated. The selection rules are derived and discussed in dependence on the polarization of the incident light.