Full electrical control of Charge and Spin conductance through Interferometry of Edge States in Topological Insulators

Abstract

We investigate electron interferometry of edge states in Topological Insulators. We show that, when inter-boundary coupling is induced at two quantum point contacts of a four terminal setup, both Fabry-Pérot-like and Aharonov-Bohm-like loop processes arise. These underlying interference effects lead to a full electrically controllable system, where the magnitude of charge and spin linear conductances can be tuned by gate voltages, without applying magnetic fields. In particular we find that, under appropriate conditions, inter-boundary coupling can lead to negative values of the conductance. Furthermore, the setup also allows to selectively generate pure charge or pure spin currents, by choosing the voltage bias configuration.

12 pages, 5 figures (expanded discussion section, corrected typos)

References in corpus (31)

• Electric Field Effect in Atomically Thin Carbon Films
• Quantum Spin Hall Effect and Topological Phase Transition in HgTe Quantum Wells
• Quantum Spin Hall Insulator State in HgTe Quantum Wells
• Topological Insulators with Inversion Symmetry
• Discovery (theoretical prediction and experimental observation) of a large-gap topological-insulator class with spin-polarized single-Dirac-cone on the surface
• A topological Dirac insulator in a quantum spin Hall phase : Experimental observation of first strong topological insulator
• Topological Field Theory of Time-Reversal Invariant Insulators
• Dissipationless Quantum Spin Current at Room Temperature
• Direct electronic measurement of the spin Hall effect
• First direct observation of Spin-textures in Topological Insulators : Spin-resolved ARPES as a probe of topological quantum spin Hall effect and Berry's phase
• Graphene field-effect-transistors with high on/off current ratio and large transport band gap at room temperature
• Quantum interference and Klein tunneling in graphene heterojunctions
• Nonlocal edge state transport in the quantum spin Hall state
• Electrical Detection of Spin Transport in Lateral Ferromagnet-Semiconductor Devices
• The Quantum Spin Hall Effect: Theory and Experiment
• The Helical Liquid and the Edge of Quantum Spin Hall Systems
• Kondo effect in the helical edge liquid of the quantum spin Hall state
• Aharonov-Bohm oscillations in disordered topological insulator nanowires
• Edge Dynamics in a Quantum Spin Hall State: Effects from Rashba Spin-Orbit Interaction
• Corner Junction as a Probe of Helical Edge States
• Tunneling between edge states in a quantum spin Hall system
• Edge-State Velocity and Coherence in a Quantum Hall Fabry-Perot Interferometer
• Tomonaga-Luttinger Liquid Features in Ballistic Single-Walled Carbon Nanotubes: Conductance and Shot Noise
• Shot Noise with Interaction Effects in Single Walled Carbon Nanotubes
• Superconductors as ideal spin sources for spintronics
• Observation of second-harmonic generation induced by pure spin currents
• Spin-resolved Quantum Interference in Graphene
• Controlling the conductance and noise of driven carbon-based Fabry-Perot devices
• AC magnetization transport and power absorption in non-itinerant spin chains
• Electron tunneling into a quantum wire in the Fabry-Perot regime
• Electron Scattering in Intrananotube Quantum Dots