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Metal-Insulator oscillations in a Two-dimensional Electron-Hole system

R. J. Nicholas·K. Takashina·M. Lakrimi·B. Kardynal·S. Khym·N. J. Mason·D. M. Symons·D. K. Maude·J. C. Portal
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Abstract

The electrical transport properties of a bipolar InAs/GaSb system have been studied in magnetic field. The resistivity oscillates between insulating and metallic behaviour while the quantum Hall effect shows a digital character oscillating from 0 to 1 conducatance quantum e^2/h. The insulating behaviour is attributed to the formation of a total energy gap in the system. A novel looped edge state picture is proposed associated with the appearance of a voltage between Hall probes which is symmetric on magnetic field reversal.

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R. J. Nicholas, K. Takashina, M. Lakrimi, B. Kardynal, S. Khym, N. J. Mason, D. M. Symons, D. K. Maude, J. C. Portal. 2000-04-11. Metal-Insulator oscillations in a Two-dimensional Electron-Hole system. https://doi.org/10.1103/physrevlett.85.2364

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