# Dual-Pump Approach to Photon-Pair Generation: Demonstration of Enhanced Characterization and Engineering Capabilities

## TL;DR

This paper demonstrates a dual-pump method for photon-pair generation that improves source characterization, enhances the purity of heralded single photons, and allows bounds on quantum state purity to be derived from photon statistics.

## Contribution

The study introduces a dual-pump technique that provides new measurement capabilities and improves the quality of photon-pair sources for quantum technologies.

## Key findings

- Enables direct measurement of noise, brightness, and efficiency from photon counts
- Improves generation of pure heralded single photons
- Allows bounds on photon state purity from photon-number statistics

## Abstract

We experimentally study the generation of photon pairs via spontaneous four-wave mixing with two distinct laser pulses. We find that the dual-pump technique enables new capabilities: 1) a new characterization methodology to measure noise contributions, source brightness and photon collection efficiencies directly from raw photon-count measurements; 2) an enhanced ability to generate heralded single photons in a pure quantum state; and 3) the ability to derive upper and lower bounds on heralded-photon quantum state purity from measurements of photon-number statistics even in the presence of noise. Such features are highly valuable in photon-pair sources for quantum applications.