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arXiv · 0809.5047

High-quality quantum point contact in two-dimensional GaAs (311)A hole system

J. Shabani·J. R. Petta·M. Shayegan
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Abstract

We studied ballistic transport across a quantum point contact (QPC) defined in a high-quality, GaAs (311)A two-dimensional (2D) hole system using shallow etching and top-gating. The QPC conductance exhibits up to 11 quantized plateaus. The ballistic one-dimensional subbands are tuned by changing the lateral confinement and the Fermi energy of the holes in the QPC. We demonstrate that the positions of the plateaus (in gate-voltage), the source-drain data, and the negative magneto-resistance data can be understood in a simple model that takes into account the variation, with gate bias, of the hole density and the width of the QPC conducting channel.

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J. Shabani, J. R. Petta, M. Shayegan. 2008-09-29. High-quality quantum point contact in two-dimensional GaAs (311)A hole system. https://doi.org/10.1063/1.3036011

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