Fragility of non-local edge mode transport in the quantum spin Hall state

Abstract

Non-local currents and voltages are better able at withstanding the deleterious effects of dephasing than local currents and voltages in nanoscale systems. This hypothesis is known to be true in quantum Hall set-ups. We test this hypothesis in a four terminal quantum spin Hall set up wherein we compare the local resistance measurement with the non-local one. In addition to inelastic scattering induced dephasing we also test resilience of the resistance measurements in the aforesaid set-ups to disorder and spin-flip scattering. We find the axiom that non-local resistance is less affected by the detrimental effects of disorder and dephasing to be in general untrue for quantum spin Hall case. This has important consequences since it has been widely communicated that non-local transport through edge channels in topological insulators will have potential applications in low power information processing.

arXiv comment7 pages, 4 figures, accepted for publication in Physical Review Applied

References in corpus (8)

• Nonlocal edge state transport in the quantum spin Hall state
• Topological Anderson Insulator
• Spin polarization of the quantum spin Hall edge states
• Probe-Configuration-Dependent Decoherence in an Aharonov-Bohm Ring
• Probe-configuration dependent dephasing in a mesoscopic interferometer
• Nonlocal Edge State Transport in Topological Insulators
• Are quantum spin Hall edge modes more resilient to disorder, sample geometry and inelastic scattering than quantum Hall edge modes?
• Multiprobe quantum spin Hall bars

Cited by in corpus (10)

• Failure of conductance quantization in two-dimensional topological insulators due to non-magnetic impurities
• Helical Liquids in Semiconductors
• Mesoscopic transport in two-dimensional topological insulators
• Probing helicity and the topological origins of helicity via non-local Hanbury-Brown and Twiss correlations
• Tunable spin-polarized edge transport in inverted quantum-well junctions
• Role of helical edge modes in the chiral quantum anomalous Hall state
• On the accuracy of conductance quantization in spin-Hall insulators
• Are thermal fluctuations the sole reason for finite longitudinal resistance in quantum anomalous Hall experiments?
• Disordered contacts can localize chiral edge electrons
• Disordered contacts can localize helical edge electrons