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arXiv · 1702.04444

Chiral anomaly and anomalous finite-size conductivity in graphene

Shun-Qing Shen·Chang-An Li·Qian Niu
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Abstract

Graphene is a monolayer of carbon atoms packed into a hexagon lattice to host two pairs of massless two-dimensional Dirac fermions in the absence of or with negligible spin-orbit coupling. It is known that the existence of non-zero electric polarization in reduced momentum space which is associated with a hidden chiral symmetry will lead to the zero-energy flat band of zigzag nanoribbon. The Adler-Bell-Jackiw chiral anomaly or non-conservation of chiral charges at different valleys can be realized in a confined ribbon of finite width. In the laterally diffusive regime, the finite-size correction to conductivity is always positive and goes inversely with the square of the lateral dimension W, which is different from the finite-size correction inversely with W from boundary modes. This anomalous finite-size conductivity reveals the signature of the chiral anomaly in graphene, and is measurable experimentally.

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Shun-Qing Shen, Chang-An Li, Qian Niu. 2017-02-15. Chiral anomaly and anomalous finite-size conductivity in graphene. https://doi.org/10.1088/2053-1583%2Faa77b9

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