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arXiv · 1801.03115

Topological Aspect of Graphene Patchwork with Regular Arrays of Nano Holes

Toshikaze Kariyado·Yongcheng Jiang·Hongxin Yang·Xiao Hu
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Abstract

Triangular and honeycomb lattices are dual to each other -- if we puncture holes into a featureless plane in a regular triangular alignment, the remaining body looks like a honeycomb lattice, and vice versa, if the holes are in a regular honeycomb alignment, the remaining body has a feature of triangular lattice. In this work, we reveal that the electronic states in graphene sheets with nano-sized holes in triangular and honeycomb alignments are also dual to each other in a topological sense. Namely, a regular hole array perforated in graphene can open a band gap in the energy-momentum dispersion of relativistic electrons in the pristine graphene, and the insulating states induced by triangular and honeycomb hole arrays are distinct in topology. In a graphene patchwork with regions of these two hole arrays put side by side counterpropagating topological currents emerge at the domain wall. This observation indicates that the cerebrated atomically thin sheet is where topological physics and nanotechnology meet.

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Toshikaze Kariyado, Yongcheng Jiang, Hongxin Yang, Xiao Hu. 2018-01-09. Topological Aspect of Graphene Patchwork with Regular Arrays of Nano Holes. https://doi.org/10.1103/physrevb.98.195416

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