Fast preparation of single hole spin in InAs/GaAs quantum dot in Voigt geometry magnetic field

TL;DR

This paper investigates rapid preparation of a single hole spin in InAs/GaAs quantum dots using a Voigt geometry magnetic field, highlighting the impact of fine-structure splitting on fidelity.

Contribution

It demonstrates the relationship between bright-exciton fine-structure splitting and spin preparation fidelity, suggesting ways to improve fidelity in quantum dot spin initialization.

Findings

Fidelity limited to 0.75 with a 17 ueV fine-structure splitting

Optimal spin preparation occurs when fine-structure matches hole Zeeman energy

Higher fidelities are possible by reducing the bright-exciton fine-structure

Abstract

The preparation of a coherent heavy-hole spin via ionization of a spin-polarized electron-hole pair in an InAs/GaAs quantum dot in a Voigt geometry magnetic field is investigated. For a dot with a 17 ueV bright-exciton fine-structure splitting, the fidelity of the spin preparation is limited to 0.75, with optimum preparation occurring when the effective fine-structure of the bright-exciton matches the in-plane hole Zeeman energy. In principle, higher fidelities can be achieved by minimizing the bright-exciton fine-structure splitting.