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

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 $\mu$eV. Our results demonstrate the viability of this platform for hybrid topological superconductor devices.

References in corpus (8)

• Majorana Fermions and a Topological Phase Transition in Semiconductor-Superconductor Heterostructures
• Transparent Semiconductor-Superconductor Interface and Induced Gap in an Epitaxial Heterostructure Josephson Junction
• Anomalous Fraunhofer Interference in Epitaxial Superconductor-Semiconductor Josephson Junctions
• Scattering mechanisms of highest-mobility InAs/Al${}_x$Ga${}_{1-x}$Sb quantum wells
• Two-subband quantum Hall effect in parabolic quantum wells
• Josephson junctions in narrow thin-film strips
• Epitaxial Superconductor-Semiconductor Two-Dimensional Systems for Superconducting Quantum Circuits
• Metamorphic InAs/InGaAs QWs with electron mobilities exceeding $7\times 10^{5}c{m}^2/Vs$

Cited by in corpus (4)

• Progress in superconductor-semiconductor topological Josephson junctions
• InAs on Insulator: A New Platform for Cryogenic Hybrid Superconducting Electronics
• Josephson Field Effect Transistors with InAs on Insulator and High Permittivity Gate Dielectrics
• Determination of the current-phase relation of an InAs 2DEG Josephson junction with a microwave resonator