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BIBTEX RIS

Quantum Hall Effect near the Charge Neutrality Point in a Two-Dimensional Electron-Hole System

2010; American Physical Society; Volume: 104; Issue: 16 Linguagem: Inglês

10.1103/physrevlett.104.166401

ISSN

1092-0145

Autores

G. M. Gusev, E. B. Olshanetsky, Z. D. Kvon, Н. Н. Михайлов, S. A. Dvoretsky, J. C. Portal,

Tópico(s)

Topological Materials and Phenomena

Resumo

We study the transport properties of HgTe-based quantum wells containing simultaneously electrons and holes in a magnetic field B. At the charge neutrality point (CNP) with nearly equal electron and hole densities, the resistance is found to increase very strongly with B while the Hall resistivity turns to zero. This behavior results in a wide plateau in the Hall conductivity sigma(xy) approximately = 0 and in a minimum of diagonal conductivity sigma(xx) at nu = nu(p) - nu(n) = 0, where nu(n) and nu(p) are the electron and hole Landau level filling factors. We suggest that the transport at the CNP point is determined by electron-hole "snake states" propagating along the nu = 0 lines. Our observations are qualitatively similar to the quantum Hall effect in graphene as well as to the transport in a random magnetic field with a zero mean value.

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