Abstract
We investigate magnetic-field-influenced time-dependent transport of Coulomb interacting electrons through a two-dimensional quantum ring in an electromagnetic cavity under nonequilibrium conditions described by a time-convolutionless non-Markovian master equation formalism. We take into account the full electromagnetic interaction of electrons and cavity photons. A bias voltage is applied to semi-infinite leads along the axis, which are connected to the quantum ring. The magnetic field is tunable to manipulate the time-dependent electron transport coupled to a photon field with either or polarization. We find that the lead-system-lead current is strongly suppressed by the -polarized photon field at magnetic field with two flux quanta due to a degeneracy of the many-body energy spectrum of the mostly occupied states. On the other hand, the lead-system-lead current can be significantly enhanced by the -polarized field at magnetic field with half-integer flux quanta. Furthermore, the -polarized photon field perturbs the periodicity of the persistent current with the magnetic field and suppresses the magnitude of the persistent current. The spatial and temporal density distributions reflect the characteristics of the many-body spectrum. The vortex formation in the contact areas to the leads influences the charge circulation in the ring.
7 More- Received 11 September 2012
DOI:https://doi.org/10.1103/PhysRevB.87.035314
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