Electrical tuning of Rashba spin-orbit interaction in multigated InAs nanowires

TL;DR

This paper demonstrates that the Rashba spin-orbit interaction in InAs nanowires can be effectively tuned by an external electric field generated by multiple gates, with a factor of two change while maintaining constant electron density.

Contribution

It introduces a method to electrostatically control the SOI in InAs nanowires using a multi-gate setup and validates the results with a simple electrostatic model.

Findings

SOI strength can be tuned by a factor of 2

Electric field controls SOI without changing electron density

Experimental results agree with the electrostatic model

Abstract

Indium arsenide (InAs) nanowires (NWs) are a promising platform to fabricate quantum electronic devices, among others they have strong spin-orbit interaction (SOI). The controlled tuning of the SOI is desired in spin based quantum devices. In this study we investigate the possibility of tuning the SOI by electrostatic field, which is generated by a back gate and two side gates placed on the opposite sides of the NW. The strength of the SOI is analyzed by weak anti-localization effect. We demonstrate that the strength of SOI can be strongly tuned by a factor of 2 with the electric field across the NW, while the average electron density is kept constant. Furthermore a simple electrostatic model is introduced to calculate the expected change of SOI. Good agreement is found between the experimental results and the estimated Rashba type SOI generated by the gate-induced electric field.