Investigation of InAs based devices for topological applications

TL;DR

This paper explores InAs-based superconductor/semiconductor devices in 1D and 2D configurations, demonstrating their tunability and potential for topological quantum applications through experimental measurements of supercurrent and spin-orbit effects.

Contribution

It provides new experimental insights into InAs devices, highlighting their tunability and suitability for topological states in quantum computing.

Findings

Supercurrent observed in InAs Josephson junctions with Nb contacts.

External gates enable control over device properties like spin-orbit length.

Multiple Andreev reflections detected in dissipative regimes.

Abstract

Hybrid superconductor/semiconductor devices constitute a powerful platform to investigate the emergence of new topological state of matter. Among all possible semiconductor materials, InAs represents a promising choice, owing to its high quality, large g-factor and spin-orbit component. Here, we report on InAs-based devices both in one-dimensional and two-dimensional configurations. In the former, low-temperature measurements on a suspended nanowire are presented, inspecting the intrinsic spin-orbit contribution of the system. In the latter, Josephson Junctions between two Nb contacts comprising an InAs quantum well are investigated. Supercurrent flow is reported, with Nb critical temperature up to T_c~8K. Multiple Andreev reflection signals are observed in the dissipative regime. In both systems, we show that the presence of external gates represents a useful knob, allowing for wide tunability and control of device properties, such as spin-orbit coherence length or supercurrent amplitude.