Fast high fidelity hole spin initialization in a single InGaAs quantum dot

TL;DR

This paper demonstrates a rapid and highly reliable method for initializing a single hole spin in an InGaAs quantum dot using magnetic fields, with fidelity exceeding 99%, highlighting the impact of exciton spin precession on fidelity.

Contribution

The study introduces a fast, high-fidelity hole spin initialization technique in quantum dots, emphasizing the effects of anisotropic exchange interaction on spin preparation.

Findings

Fidelity of >99% in hole spin initialization

Precession of exciton spin limits fidelity

Magnetic field applied parallel to growth direction

Abstract

We demonstrate fast initialization of a single hole spin captured in an InGaAs quantum dot with a fidelity F>99% by applying a magnetic field parallel to the growth direction. We show that the fidelity of the hole spin, prepared by ionization of a photo-generated electron-hole pair, is limited by the precession of the exciton spin due to the anisotropic exchange interaction.