Impact of a circularly polarized cavity photon field on the charge and spin flow through an Aharonov-Casher ring
arXiv:1311.3235 · doi:10.1016/j.physe.2014.02.024
Abstract
We explore the influence of a circularly polarized cavity photon field on the transport properties of a finite-width ring, in which the electrons are subject to spin-orbit and Coulomb interaction. The quantum ring is embedded in an electromagnetic cavity and described by ``exact'' numerical diagonalization. We study the case that the cavity photon field is circularly polarized and compare it to the linearly polarized case. The quantum device is moreover coupled to external, electrically biased leads. The time propagation in the transient regime is described by a non-Markovian generalized master equation. We find that the spin polarization and spin photocurrents of the quantum ring are largest for circularly polarized photon field and destructive Aharonov-Casher (AC) phase interference. The charge current suppression dip due to the destructive AC phase becomes threefold under the circularly polarized photon field as the interaction of the electrons' angular momentum and spin angular momentum of light causes many-body level splitting leading to three many-body level crossing locations instead of one. The circular charge current inside the ring, which is induced by the circularly polarized photon field, is found to be suppressed in a much wider range around the destructive AC phase than the lead-device-lead charge current. The charge current can be directed through one of the two ring arms with the help of the circularly polarized photon field, but is superimposed by vortices of smaller scale. Unlike the charge photocurrent, the flow direction of the spin photocurrent is found to be independent of the handedness of the circularly polarized photon field.
References in corpus (13)
- Full Counting Statistics in Strongly Interacting Systems: Non-Markovian Effects
- Optimal Control of Quantum Rings by Terahertz Laser Pulses
- Persistent spin current in nano-devices and definition of the spin current
- Staying positive: going beyond Lindblad with perturbative master equations
- Laser-controlled local magnetic field with semiconductor quantum rings
- Equilibrium spin currents in the Rashba medium
- Mechanical measurement of equilibrium spin currents in the Rashba medium
- Persistent current induced by vacuum fluctuations in a quantum ring
- Coherent quantum transport in narrow constrictions in the presence of a finite-range longitudinally polarized time-dependent field
- Magnetic-field influenced non-equilibrium transport through a quantum ring with correlated electrons in a photon cavity
- Coherent quantum transport in the presence of a finite-range transversely polarized time-dependent field
- Polarized light bursts from kicked quantum rings
- Geometry and linearly polarized cavity photon effects on the charge and spin currents of spin-orbit interacting electrons in a quantum ring
Cited by in corpus (6)
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- Photon-induced tunability of the thermospin current in a Rashba ring
- Single-photon controlled thermospin transport in a resonant ring-cavity system
- Excitation spectra of a quantum ring embedded in a photon cavity
- Generalized Master Equation Approach to Time-Dependent Many-Body Transport
- Lamb Shift of Energy Levels in Quantum Rings