# Are quantum spin Hall edge modes more resilient to disorder, sample geometry and inelastic scattering than quantum Hall edge modes?

@article{Mani2016AreQS, title={Are quantum spin Hall edge modes more resilient to disorder, sample geometry and inelastic scattering than quantum Hall edge modes?}, author={Arjun Mani and Colin Benjamin}, journal={Journal of physics. Condensed matter : an Institute of Physics journal}, year={2016}, volume={28 14}, pages={ 145303 } }

On the surface of 2D topological insulators, 1D quantum spin Hall (QSH) edge modes occur with Dirac-like dispersion. Unlike quantum Hall (QH) edge modes, which occur at high magnetic fields in 2D electron gases, the occurrence of QSH edge modes is due to spin-orbit scattering in the bulk of the material. These QSH edge modes are spin-dependent, and chiral-opposite spins move in opposing directions. Electronic spin has a larger decoherence and relaxation time than charge. In view of this, it is…

## 9 Citations

Probing helicity and the topological origins of helicity via non-local Hanbury-Brown and Twiss correlations

- Physics, MedicineScientific Reports
- 2017

This work reports on the advantage of using the non local shot noise as a probe for the helical nature of these states as also their topological or otherwise origin and compares them with chiral quantum Hall states.

Disordered contacts can localize chiral edge electrons

- Physics
- 2020

Abstract Chiral integer quantum Hall (QH) edge modes are immune to backscattering and therefore are non-localized and show a vanishing longitudinal as well as non-local resistance along with…

Disordered contacts can localize helical edge electrons.

- Medicine, PhysicsJournal of physics. Condensed matter : an Institute of Physics journal
- 2019

This paper shows that when all contacts are disordered in a N-terminal QSH sample, then transport via these helical QSH edge modes can have a significant localization correction.

Role of helical edge modes in the chiral quantum anomalous Hall state

- Physics, MedicineScientific Reports
- 2018

It is shown in similar set-ups affected by disorder and inelastic scattering, transport via trivial QAH edge mode leads to quantization of Hall resistance and not that via topologicalQAH edge modes.

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

- Physics
- 2016

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…

On the Accuracy of Conductance Quantization in Spin-Hall Insulators

- PhysicsJETP Letters
- 2019

In contrast to the case of ordinary quantum Hall effect, the resistance of ballistic helical edge channels in typical quantum spin-Hall experiments is non-vanishing, additive and poorly quantized.…

Are thermal fluctuations the sole reason for finite longitudinal resistance in quantum anomalous Hall experiments?

- Physics, MedicineJournal of physics. Condensed matter : an Institute of Physics journal
- 2018

It is shown that similar effects arise in QAH samples with quasi-helical edge modes as disorder increases in the presence or absence of inelastic scattering even at temperature T’s higher than 0.05C.

Local equilibrium charge and spin currents in two-dimensional topological systems

- Physics
- 2021

We study the equilibrium and nonequilibrium electronic transport properties of multiprobe topological systems using a combination of the Landauer-Büttiker approach and nonequilibrium Green’s…

Quantum localization correction to chiral edge mode transport

- Physics
- 2018

We answer the question- Can chiral quantum Hall edge modes suffer localization? in the affirmative. Hitherto, only seen in quantum diffusive transport, a quantum localization correction arises in the…

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