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arXiv · 1704.08954

Volkov-Pankratov states in topological heterojunctions

S. Tchoumakov·V. Jouffrey·A. Inhofer·E. Bocquillon·B. Plaçais·D. Carpentier·M. O. Goerbig
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Abstract

We show that a smooth interface between two insulators of opposite topological Z2 indices possesses multiple surface states, both massless and massive. While the massless surface state is non-degenerate, chiral and insensitive to the interface potential, the massive surface states only appear for a sufficiently smooth heterojunction. The surface states are particle-hole symmetric and a voltage drop reveals their intrinsic relativistic nature, similarly to Landau bands of Dirac electrons in a magnetic field. We discuss the relevance of the massive Dirac surface states in recent ARPES and transport experiments.

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S. Tchoumakov, V. Jouffrey, A. Inhofer, E. Bocquillon, B. Plaçais, D. Carpentier, M. O. Goerbig. 2017-04-28. Volkov-Pankratov states in topological heterojunctions. https://doi.org/10.1103/physrevb.96.201302

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