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arXiv · 1205.7070

Nonlocal transport near the charge neutrality point in a two-dimensional electron-hole system

G. M. Gusev·E. B. Olshanetsky·Z. D. Kvon·A. D. Levin·N. N. Mikhailov·S. A. Dvoretsky
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Abstract

Nonlocal resistance is studied in a two-dimensional system with a simultaneous presence of electrons and holes in a 20 nm HgTe quantum well. A large nonlocal electric response is found near the charge neutrality point (CNP) in the presence of a perpendicular magnetic field. We attribute the observed nonlocality to the edge state transport via counter propagating chiral modes similar to the quantum spin Hall effect at zero magnetic field and graphene near Landau filling factor $ν=0$

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G. M. Gusev, E. B. Olshanetsky, Z. D. Kvon, A. D. Levin, N. N. Mikhailov, S. A. Dvoretsky. 2012-05-31. Nonlocal transport near the charge neutrality point in a two-dimensional electron-hole system. https://doi.org/10.1103/physrevlett.108.226804

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