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arXiv · 2206.10984

Near-surface InAs 2DEG on a GaAs substrate: characterization and superconducting proximity effect

Máté Sütő·Tamás Prok·Péter Makk·Magdhi Kirti·Giorgio Biasiol·Szabolcs Csonka·Endre Tóvári
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Abstract

We have studied a near-surface two-dimensional electron gas based on an InAs quantum well on a GaAs substrate. In devices without a dielectric layer we estimated large electron mobilities on the order of $10^5$ cm$^2$/Vs. We have observed quantized conductance in a quantum point contact, and determined the g-factor. Using samples with an epitaxial Al layer, we defined multiple Josephson junctions and found the critical current to be gate tunable. Based on multiple Andreev reflections the semiconductor-superconductor interface is transparent, with an induced gap of 125 $μ$eV. Our results demonstrate the viability of this platform for hybrid topological superconductor devices.

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Máté Sütő, Tamás Prok, Péter Makk, Magdhi Kirti, Giorgio Biasiol, Szabolcs Csonka, Endre Tóvári. 2023-03-17. Near-surface InAs 2DEG on a GaAs substrate: characterization and superconducting proximity effect. https://doi.org/10.1103/physrevb.106.235404

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