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arXiv · 1906.01995

A Gate-Defined Quantum Point Contact in an InAs Two-Dimensional Electron Gas

Christopher Mittag·Matija Karalic·Zijin Lei·Candice Thomas·Aymeric Tuaz·Anthony T. Hatke·Geoffrey C. Gardner·Michael J. Manfra·Thomas Ihn·Klaus Ensslin
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Abstract

We experimentally study quantized conductance in an electrostatically defined constriction in a high-mobility InAs two-dimensional electron gas. A parallel magnetic field lifts the spin degeneracy and allows for the observation of plateaus in integer multiples of $e^2/h$. Upon the application of a perpendicular magnetic field, spin-resolved magnetoelectric subbands are visible. Through finite bias spectroscopy we measure the subband spacings in both parallel and perpendicular direction of the magnetic field and determine the $g$-factor.

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Christopher Mittag, Matija Karalic, Zijin Lei, Candice Thomas, Aymeric Tuaz, Anthony T. Hatke, Geoffrey C. Gardner, Michael J. Manfra, Thomas Ihn, Klaus Ensslin. 2019-08-02. A Gate-Defined Quantum Point Contact in an InAs Two-Dimensional Electron Gas. https://doi.org/10.1103/physrevb.100.075422

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