# Topological valley transport at bilayer graphene domain walls

@article{Ju2015TopologicalVT, title={Topological valley transport at bilayer graphene domain walls}, author={Long Ju and Zhiwen Shi and Nityan L. Nair and Yinchuan Lv and Chenhao Jin and Jairo Velasco and Claudia Ojeda-Aristizabal and Hans A. Bechtel and Michael C. Martin and Alex Zettl and James G. Analytis and Feng Wang}, journal={Nature}, year={2015}, volume={520}, pages={650-655} }

Electron valley, a degree of freedom that is analogous to spin, can lead to novel topological phases in bilayer graphene. A tunable bandgap can be induced in bilayer graphene by an external electric field, and such gapped bilayer graphene is predicted to be a topological insulating phase protected by no-valley mixing symmetry, featuring quantum valley Hall effects and chiral edge states. Observation of such chiral edge states, however, is challenging because inter-valley scattering is induced…

## 427 Citations

### Nanoscale strain engineering of giant pseudo-magnetic fields, valley polarization, and topological channels in graphene

- PhysicsScience Advances
- 2020

By placing strain-free monolayer graphene on architected nanostructures to induce global inversion symmetry breaking, this work demonstrates the development of giant pseudo-magnetic fields, valley polarization, and periodic one-dimensional topological channels for protected propagation of chiral modes in strained graphene, thus paving a pathway toward scalable graphene-based valleytronics.

### Interplay between topological valley and quantum Hall edge transport

- PhysicsNature communications
- 2022

An established way of realising topologically protected states in a two-dimensional electron gas is by applying a perpendicular magnetic field thus creating quantum Hall edge channels. In…

### Edge states in gated bilayer-monolayer graphene ribbons and bilayer domain walls

- PhysicsJournal of Applied Physics
- 2018

Using the effective continuum model, the electron energy spectrum of gated bilayer graphene with a step-like region of decoupled graphene layers at the edge of the sample is studied. Different types…

### Soliton-dependent Electronic Transport across Bilayer Graphene Domain Wall.

- PhysicsNano letters
- 2020

The first experimental observation of electronic transport across bilayer graphene domain walls is reported by combining near-field infrared nanoscopy and scanning voltage microscopy techniques, observing markedly different electron transport behaviors across the tensile- and shear-type domain walls.

### Observation of chiral edge states in gapped nanomechanical graphene

- PhysicsScience Advances
- 2021

This work experimentally realized quantum valley Hall chiral edge states in nanomechanical graphene by tuning the boundary potentials and experimentally demonstrated that they are backscattering-immune against sharp bends and exhibit the “valley-momentum locking” effect.

### Topological valley transport at the curved boundary of a folded bilayer graphene

- PhysicsCommunications Physics
- 2019

The development of valleytronics demands long-range electronic transport with preserved valley index, a degree of freedom similar to electron spin. A promising structure for this end is a topological…

### Existence of nontrivial topologically protected states at grain boundaries in bilayer graphene: signatures and electrical switching.

- PhysicsNanoscale
- 2016

This work shows that the appearance of the topologically protected states in stacking domain walls can be much more common in bilayer graphene, since they can also emerge in unexpected geometries, e.g., at grain boundaries with atomic-scale topological defects.

### Plasmon Reflections by Topological Electronic Boundaries in Bilayer Graphene.

- PhysicsNano letters
- 2017

It is shown that strong coupling of domain walls to surface plasmons observed in infrared nanoimaging experiments is due to topological chiral modes confined to the walls, which enhances the local conductivity and leads to plasmon reflection by the domain walls.

### Spatial variation of energy gap and Landau levels around gapped bilayer graphene domain walls

- Physics
- 2015

Bilayer graphene contains, compared to graphene monolayer, an additional graphene sheet and, therefore, extra degrees of freedom, making it a unique system for complex electronic states to emerge.…

### Direct imaging of topological edge states at a bilayer graphene domain wall

- PhysicsNature communications
- 2016

This experiment demonstrates that the one-dimensional topological states of graphene bilayer domain wall are quite robust even in the presence of high magnetic fields, and may raise hopes of graphene-based electronics with ultra-low dissipation.

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