Entangled photons survive a 38 mile ride through fiber-optic cable strung above Maryland streets

Entangled photons survive a 38 mile ride through fiber-optic cable strung above Maryland streets

Entangled photons stayed connected after traveling 62 kilometers through mostly aboveground fiber between NIST and the University of Maryland. A real-time correction system tracked changes in the fiber and reversed distortions before they could overwhelm the quantum signal. The test shows existing communications infrastructure may support future quantum networks, although photon loss, speed and faster stabilization remain challenges. Quantum sig…