Andreev reflection in two-dimensional topological insulators with either conserved or broken time-reversal symmetry

Abstract

We investigate Andreev reflection in two-dimensional heterojunctions formed by a superconductor in contact with a topological insulator ribbon either possessing or breaking time-reversal symmetry. Both classes of topological insulators exhibit perfect Andreev reflection, which is robust against disorder. This is assigned to topologically protected edge states. In the time-reversal symmetric case we show that doping one of the ribbon edges with magnetic impurities suppresses one Andreev channel, while no such suppression is seen in the broken symmetry situation. Based on this observation we suggest a tabletop transport experiment able to distinguish between the two types of topological insulators, which does not involve the direct measurement of the material band structure.

Updated text, references added, published version

References in corpus (14)

• Topological Insulators
• Topological insulators and superconductors
• Quantum Spin Hall Effect and Topological Phase Transition in HgTe Quantum Wells
• Superconducting proximity effect and Majorana fermions at the surface of a topological insulator
• 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
• Quantized Anomalous Hall Effect in Magnetic Topological Insulators
• Quantum Anomalous Hall Effect in Hg${}_{1-y}$Mn${}_y$Te Quantum Wells
• Quantum Anomalous Hall Effect in Graphene from Rashba and Exchange Effects
• Time-reversal-symmetry-broken quantum spin Hall effect
• Non-equilibrium Green s function based model for dephasing in quantum transport
• Probing the helical edge states of a topological insulator by Cooper-pair injection
• High Chern number quantum anomalous Hall phases in graphene ribbons with Haldane orbital coupling
• Quantum Andreev effect in 2D HgTe/CdTe quantum well-superconductor systems

Cited by in corpus (12)

• Devices with electrically tunable topological insulating phases
• Quantum interference in topological insulator Josephson junctions
• High-Efficiency Cooper-Pair Splitter in Quantum Anomalous Hall Insulator Proximity-Coupled with Superconductor
• Density-dependent thermopower oscillations in mesoscopic two-dimensional electron gases
• Spin-pumping and inelastic electron tunneling spectroscopy in topological insulators
• Single atom anisotropic magnetoresistance on a topological insulator surface
• Identifying Majorana bound states at quantum spin Hall edges using a metallic probe
• Multiprobe quantum spin Hall bars
• Gate controlled spin pumping at a quantum spin Hall edge
• Parity-protected superconducting qubit based on topological insulators
• Bulk transport through superconducting hybrid structures in HgTe quantum wells
• Spin-dependent Andreev reflection in spin-orbit coupled systems by breaking time-reversal symmetry