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arXiv · 2011.02951

Gate-defined Quantum Point Contact in an InSb Two-dimensional Electron Gas

Zijin Lei·Christian A. Lehner·Erik Cheah·Christopher Mittag·Matija Karalic·Werner Wegscheider·Klaus Ensslin·Thomas Ihn
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Abstract

We investigate an electrostatically defined quantum point contact in a high-mobility InSb two-dimensional electron gas. Well-defined conductance plateaus are observed, and the subband structure of the quantum point contact is extracted from finite-bias measurements. The Zeeman splitting is measured in both in-plane and out-of-plane magnetic fields. We find an in-plane g factor $|g_{\parallel}^* | \approx$ 40. The out-of-plane g factor is measured to be $|g_{\perp}^* | \approx$ 50, which is close to the g factor in the bulk.

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Zijin Lei, Christian A. Lehner, Erik Cheah, Christopher Mittag, Matija Karalic, Werner Wegscheider, Klaus Ensslin, Thomas Ihn. 2020-11-05. Gate-defined Quantum Point Contact in an InSb Two-dimensional Electron Gas. https://doi.org/10.1103/physrevresearch.3.023042

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