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arXiv · 1809.04036

Topological Zero-Line Modes in Folded Bilayer Graphene

Tao Hou·Guanghui Chen·Wang-Kong Tse·Changgan Zeng·Zhenhua Qiao
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Abstract

We theoretically investigate a folded bilayer graphene structure as an experimentally realizable platform to produce the one-dimensional topological zero-line modes. We demonstrate that the folded bilayer graphene under an external gate potential enables tunable topologically conducting channels to be formed in the folded region, and that a perpendicular magnetic field can be used to enhance the conducting when external impurities are present. We also show experimentally that our proposed folded bilayer graphene structure can be fabricated in a controllable manner. Our proposed system greatly simplifies the technical difficulty in the original proposal by considering a planar bilayer graphene (i.e., precisely manipulating the alignment between vertical and lateral gates on bilayer graphene), laying out a new strategy in designing practical low-power electronics by utilizing the gate induced topological conducting channels.

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Tao Hou, Guanghui Chen, Wang-Kong Tse, Changgan Zeng, Zhenhua Qiao. 2018-09-11. Topological Zero-Line Modes in Folded Bilayer Graphene. https://doi.org/10.1103/physrevb.98.245417

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