Engineers transmit quantum data on everyday internet fiber cables

Engineers at the University of Pennsylvania have demonstrated that quantum signals can be transmitted over commercial fiber-optic internet cables alongside classical data using the same internet protocol (IP) that powers today’s web. Their innovation centers on a silicon “Q-chip” that pairs a measurable classical light signal with fragile quantum particles, allowing the classical signal to guide routing without disturbing the quantum information. This approach enables quantum and classical data to be packaged together and routed through existing internet infrastructure, achieving over 97% signal fidelity in tests conducted on Verizon’s live fiber network. The Q-chip’s design addresses a major challenge in scaling quantum networks: quantum particles collapse when measured, making traditional data routing methods unusable. By sending a classical “header” signal ahead of the quantum data, the system can perform routing and error correction without directly measuring the quantum states. The chip’s silicon-based fabrication allows for mass production and integration into current networks, though distance limitations remain since quantum signals cannot yet be amplified without loss. The researchers liken