Continuous monitoring can improve indistinguishability of a single-photon source

TL;DR

This paper proposes a continuous quantum measurement and feed-forward control technique to enhance the indistinguishability of photons emitted from a single-photon source by reducing emission time uncertainty.

Contribution

It introduces a novel method combining continuous monitoring and feed-forward control to improve photon indistinguishability in quantum emitters.

Findings

Improved photon indistinguishability through continuous monitoring.

Reduction of emission time uncertainty in weak coupling regime.

Enhanced control over photon emission timing.

Abstract

A new engineering technique using continuous quantum measurement in conjunction with feed-forward is proposed to improve indistinguishability of a single-photon source. The technique involves continuous monitoring of the state of the emitter, processing the noisy output signal with a simple linear estimation algorithm, and feed forward to control a variable delay at the output. In the weak coupling regime, the information gained by monitoring the state of the emitter is used to reduce the time uncertainty inherent in photon emission from the source, which improves the indistinguishability of the emitted photons.