Northwestern University engineers have achieved the first demonstration of quantum teleportation over fiber optic cables transporting conventional internet data. This breakthrough, led by Professor Prem Kumar, combines quantum and classical communications seamlessly using existing infrastructure. Kumar explained that the work demonstrates how quantum networks and classical networks can share the same fiber optic framework.
“It opens the door to pushing quantum communications to the next level,” he stated. Quantum teleportation relies on quantum entanglement, a phenomenon where two particles become interconnected, allowing information transfer without physical transmission. This method enables ultra-secure communication, as it does not require data to traverse the distance between sender and receiver.
To realize this feat, Kumar and his team overcame challenges associated with the entangled particles being washed out by other Internet traffic. They identified a less congested wavelength of 1290 nanometers, distinct from the heavily trafficked C-band at 1547 nanometers. Through a setup involving a 30.2-kilometer fiber optic cable, the team simultaneously transmitted quantum information alongside 400 Gbps Internet traffic.
Quantum progress in fiber optics
They performed quantum measurements midway and verified that the quantum state was successfully teleported, proving the durability of the entanglement amid busy traffic. “This ability to send information without direct transmission opens the door for even more advanced quantum applications being performed without dedicated fiber,” said Jordan Thomas, a Ph.D. candidate and lead author of the study.
While this experiment served primarily as proof of concept, future innovations may lead to practical quantum communication applications. Next steps for the team include extending the experimental range and employing multiple pairs of entangled photons—an approach called entanglement swapping. One notable aspect of this progress is its potential reflection on security measures in communications, offering a method to transmit data impervious to interception.
“If we choose the wavelengths properly, we won’t have to build a new infrastructure. Classical communications and quantum communications can coexist,” Kumar pointed out. This achievement, while significant, still requires further research and refinement before it can translate into practical applications.
As quantum technologies continue to evolve, the implications of this work could redefine the landscape of secure communication.
