High-rate sub-GHz linewidth bichromatic entanglement source for quantum networking

TL;DR

This paper presents a high-rate, fiber-compatible entanglement source based on four-wave mixing in rubidium vapor, achieving over 10 million pairs per second, advancing quantum networking capabilities.

Contribution

It introduces a novel operating regime for entanglement generation in rubidium vapor, achieving unprecedented pair rates and compatibility with telecom infrastructure.

Findings

Achieved over 10^7 entangled pairs per second.

Demonstrated non-degenerate photon pairs at 795 nm and 1324 nm.

Validated the source's compatibility with quantum networks.

Abstract

The generation of entangled photon pairs which are compatible with quantum devices and standard telecommunication channels are critical for the development of long range fiber quantum networks. Aside from wavelength, bandwidth matching and high fidelity of produced pairs are necessary for high interfacing efficiency. High-rate, robust entanglement sources that satisfy all these conditions remain an outstanding experimental challenge. In this work, we study an entanglement source based on four-wave mixing in a diamond configuration in a warm rubidium vapor. We theoretically and experimentally investigate a new operating regime and demonstrate an entanglement source which produces highly non-degenerate $795$ and $1324$-nm photon pairs. With this source we are able to achieve in-fiber entangled pair generation rates greater than $10^7\, /s$, orders of magnitude higher than previously reported atomic sources. Additionally, given our source's native compatibility with telecom infrastructure and atomic systems, it is an important step towards scalable quantum networks.