Spin-selective resonant tunneling induced by Rashba spin-orbit interaction in semiconductor nanowire

TL;DR

This paper demonstrates a high-fidelity, all-electrical method for spin-selective resonant tunneling in semiconductor nanowires using Rashba spin-orbit interaction, enabling efficient spin initialization and readout for quantum computing.

Contribution

It introduces a novel technique utilizing time-varying electric fields to induce Rashba coupling for spin-dependent tunneling with over 99.5% fidelity.

Findings

Achieved over 99.5% fidelity in spin-dependent tunneling.

Proposed a method for adiabatic spin initialization and readout.

Supported results with realistic self-consistent simulations.

Abstract

We consider a single electron confined within a quantum wire in a system of two electrostatically-induced QDs defined by nearby gates. The time-varying electric field, of single GHz frequency, perpendicular to the quantum wire, is used to induce the Rashba coupling and enable spin-dependent resonant tunneling of the electron between two adjacent potential wells with fidelity over 99.5%. This effect can be used for the high fidelity all-electrical electron-spin initialization or readout in the spin-based quantum computer. In contrast to other spin initialization methods, our technique can be performed adiabatically without increase in the energy of the electron. Our simulations are supported by a realistic self-consistent time-dependent Poisson-Schroedinger calculations.