Coherent transient transport of interacting electrons through a quantum waveguide switch

Abstract

We investigate coherent electron-switching transport in a double quantum waveguide system in a perpendicular static or vanishing magnetic field. The finite symmetric double waveguide is connected to two semi-infinite leads from both ends. The double waveguide can be defined as two parallel finite quantum wires or waveguides coupled via a window to facilitate coherent electron inter-wire transport. By tuning the length of the coupling window, we observe oscillations in the net charge current and a maximum electron conductance for the energy levels of the two waveguides in resonance. The importance of the mutual Coulomb interaction between the electrons and the influence of two-electron states is clarified by comparing results with and without the interaction. Even though the Coulomb interaction can lift two-electron states out of the group of active transport states the length of the coupling window can be tuned to locate two very distinct transport modes in the system in the late transient regime before the onset of a steady state. A static external magnetic field and quantum-dots formed by side gates (side quantum dots) can be used to enhance the inter-waveguide transport which can serve to implement a quantum logic device. The fact that the device can be operated in the transient regime can be used to enhance its speed.

References in corpus (11)

• Quantum Computation with Ballistic Electrons
• Geometrical effects and signal delay in time-dependent transport at the nanoscale
• Coulomb interaction and transient charging of excited states in open nanosystems
• Time-dependent transport via the generalized master equation through a finite quantum wire with an embedded subsystem
• Stepwise introduction of model complexity in a generalized master equation approach to time-dependent transport
• Time-dependent magnetotransport in an interacting double quantum wire with window coupling
• Theory of semiconductor quantum-wire based single- and two-qubit gates
• Electron transport through a quantum dot assisted by cavity photons
• Coulomb entangler and entanglement testing network for waveguide qubits
• Spin-Orbit Qubit on a Multiferroic Insulator in a Superconducting Resonator
• Correlated time-dependent transport through a 2D quantum structure

Cited by in corpus (6)

• Optical switching of electron transport in a waveguide-QED system
• Manifestation of the Purcell effect in current transport through a dot-cavity-QED system
• Single-photon controlled thermospin transport in a resonant ring-cavity system
• Cavity-photon-switched coherent transient transport in a double quantum waveguide
• Reconfigurable quantum logic gates using Rashba controlled spin polarized currents
• Electric-Field Control of Bound States and Optical Spectrum in Window-Coupled Quantum Waveguides