# Single-Photon Distillation via a Photonic Parity Measurement Using Cavity QED

## TL;DR

This paper presents a method to generate high-fidelity single photons with tailored profiles using cavity QED and atomic measurements, advancing quantum network resources.

## Contribution

We introduce a photon distillation technique employing a photonic parity measurement in cavity QED, achieving high-fidelity single photons from shaped laser pulses.

## Key findings

- Single photons with 66% fidelity were produced.
- Two-photon suppression reached 95.5%.
- Negative Wigner function value of -0.125 was observed.

## Abstract

Single photons with tailored temporal profiles are a vital resource for future quantum networks. Here we distill them out of custom-shaped laser pulses that reflect from a single atom strongly coupled to an optical resonator. A subsequent measurement on the atom is employed to herald a successful distillation. Out of vacuum-dominated light pulses, we create single photons with fidelity $66(1)\%$, two-and-more-photon suppression $95.5(6)\%$, and a Wigner function with negative value $-0.125(6)$. Our scheme applied to state-of-the-art fiber resonators could boost the single-photon fidelity to up to $96\%$.