Entangled Photons Maintained Under New York Streets

Researchers have successfully transmitted large numbers of entangled photons through a 34-km fiber-optic network in New York City, achieving a high fidelity of 99%. This advancement is crucial for the development of secure quantum networks, which require the reliable distribution of entangled photons. The team, led by Mehdi Namazi from Qunnect, demonstrated the ability to send 20,000 entangled photons per second continuously for two weeks without the frequent recalibrations that previous systems required. The challenge of maintaining photon entanglement in optical fibers, which are susceptible to various stresses, was addressed by measuring polarization drift across different wavelengths and compensating for these variations. The photons were generated using a rubidium vapor, producing pairs of photons that were sent through the fiber. The system achieved an impressive uptime of 99.84%, marking a significant step toward the commercialization of quantum networks. Experts in the field have noted that this work represents a major advancement in deploying quantum networks in real-world applications, as it minimizes downtime and enhances operational efficiency.

- Researchers transmitted 20,000 entangled photons per second with 99% fidelity.

- The system operated continuously for two weeks without recalibration.

- The project utilized a 34-km fiber-optic network in New York City.

- Polarization drift was measured and compensated to maintain entanglement.

- This work is a significant step toward practical quantum network deployment.