Magnetic-field influenced non-equilibrium transport through a quantum ring with correlated electrons in a photon cavity

TL;DR

This study explores how magnetic fields and photon polarization influence non-equilibrium electron transport in a quantum ring, revealing significant current modulation effects due to electromagnetic interactions and magnetic flux tuning.

Contribution

It presents a comprehensive non-Markovian quantum transport model that includes full electron-photon interactions without approximations, applied to a quantum ring system.

Findings

Y-polarized photons suppress current at two flux quanta.

Y-polarized photons enhance current at half-integer flux quanta.

Magnetic flux and photon polarization can control electron transport.

Abstract

We investigate magnetic-field influenced time-dependent transport of Coulomb interacting electrons through a two-dimensional quantum ring in an electromagnetic cavity under non-equilibrium conditions described by a time-convolutionless non-Markovian master equation formalism. We take into account the full electromagnetic interaction of electrons and cavity photons without resorting to the rotating wave approximation or reduction to two levels. A bias voltage is applied to semi-infinite leads along the x-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 x- or y-polarization. We find that the lead-system-lead current is strongly suppressed by the y-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. Furthermore, the current can be significantly enhanced by the y-polarized field at magnetic field with half integer flux quanta.