Gate tunable parallel double quantum dot in InAs double-nanowire junctions

TL;DR

This paper demonstrates the fabrication and measurement of a gate-tunable parallel double quantum dot system in InAs nanowire junctions, enabling advanced quantum experiments like Cooper-pair splitting.

Contribution

It introduces a novel fabrication technique for parallel double quantum dots in InAs nanowires with tunable electrostatic coupling.

Findings

Confirmed formation of parallel double quantum dots in InAs nanowires.

Achieved tunable electrostatic coupling between the quantum dots.

Device fabrication method enables future quantum experiments.

Abstract

We report fabrication and measurement of a device where closely-placed two parallel InAs nanowires (NWs) are contacted by source and drain normal metal electrodes. Established technique includes selective deposition of double nanowires onto a previously defined gate region. By tuning the junction with the finger bottom gates, we confirmed the formation of parallel double quantum dots, one in each NW, with a finite electrostatic coupling between each other. With the fabrication technique established in this study, devices proposed for more advanced experiments, such as Cooper-pair splitting and the observation of parafermions, can be realized.