All-optical non-demolition measurement of single-hole spin in a quantum-dot molecule

TL;DR

This paper proposes an all-optical, high-fidelity method for non-demolition measurement of a single hole spin in a quantum-dot molecule, enabling rapid measurement and spin manipulation without magnetic fields.

Contribution

It introduces a novel all-optical scheme for non-demolition measurement of a single hole spin in a quantum-dot molecule, achieving fast, high-fidelity results and enabling spin oscillation observation.

Findings

Measurement completed within 100 ps, faster than T2.

High fidelity of the measurement process.

Scheme enables observation of spin oscillations without magnetic fields.

Abstract

We propose an all-optical scheme to perform a non-demolition measurement of a single hole spin localized in a quantum-dot molecule. The latter is embedded in a microcavity and driven by two lasers. This allows to induce Raman transitions which entangle the spin state with the polarization of the emitted photons. We find that the measurement can be completed with high fidelity on a timescale of 100 ps, shorter than the typical T2. Furthermore, we show that the scheme can be used to induce and observe spin oscillations without the need of time-dependent magnetic fields.