Dynamics of the non-classical light from a single solid-state quantum emitter

TL;DR

This paper investigates the real-time dynamics of non-classical light emitted by a quantum dot, revealing how photon purity and coherence vary during excitation and decay cycles using two-time correlations.

Contribution

It introduces a method combining two-time correlations with pulsed excitation to analyze single-photon purity and coherence dynamics in solid-state emitters.

Findings

Photon purity and coherence vary during the emission cycle.

Early emitted photons have reduced purity and coherence.

Exciton recapture influences photon purity dynamics.

Abstract

We measure the dynamics of a non-classical optical field using two-time second-order correlations in conjunction with pulsed excitation. The technique quantifies single-photon purity and coherence during the excitation-decay cycle of an emitter, illustrated here using a quantum dot. We observe that for certain pump wavelengths, photons detected early in the cycle have reduced single-photon purity and coherence compared to those detected later. A model indicates that the single-photon purity dynamics are due to exciton recapture after initial emission and within the same pulse cycle.