Chiral Surface Modes in Three-Dimensional Topological Insulators

Kiminori Hattori; Hiroaki Okamoto

doi:10.7566/jpsj.85.053707

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arXiv · 1601.01091

Chiral Surface Modes in Three-Dimensional Topological Insulators

Kiminori Hattori·Hiroaki Okamoto

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Abstract

Where chiral modes should appear is an essential question for the quantum anomalous Hall (QAH) effect in three-dimensional topological insulators (3DTIs). In this Letter, we show that in a slab of ferromagnetic 3DTI subjected to a uniform exchange field normal to its top and bottom surfaces, the QAH effect creates a single chiral surface mode delocalized on the side faces. In a nonmagnetic 3DTI, analogously, delocalized helical modes consisting of a pair of oppositely propagating chiral surface modes are produced by the quantum spin Hall effect.

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Kiminori Hattori, Hiroaki Okamoto. 2016-01-06. Chiral Surface Modes in Three-Dimensional Topological Insulators. https://doi.org/10.7566/jpsj.85.053707

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