Effects of magnetic and electric fields on the excitonic properties of quantum rings

We have studied the effects of an external electric field on the excitonic and optical spectra of a semiconductor quantum ring threaded by a magnetic flux. We have make a detailed analysis of the ground-state properties of radially polarized excitons and its dependence with magnetic fields applied perpendicular to the ring plane and electric fields parallel to the ring plane. In the absence of the electric field, the total angular momentum of the polarized exciton remains a good quantum number, even in the interacting regime, as a consequence of the Coulomb interaction only depends on the relative coordinate and the azimuthal rotational symmetry of the structured rings. The electric field breaks the azimuthal symmetry and mixes the eigenfunctions with differents angular momentum. For the extended regimen we have found that the electric field destroys the oscillations of the ground-state energy as a function of the magnetic field. The low-lying energy levels are almost independent of the magnetic field up to a region in energy where periodic Aharonov-Bohm-type oscillations appear.