In a remarkable breakthrough, researchers in the United States have successfully teleported a quantum state of light across more than 30 kilometers (around 18 miles) of fiber optic cable — even as the cable was busy carrying regular internet traffic. This achievement, once thought impossible, marks a significant milestone in the quest for quantum communication.
While this doesn’t mean you’ll be teleporting to the office or streaming cat videos at light speed anytime soon, the implications are profound. Successfully transmitting quantum information through existing fiber optic infrastructure opens the door to ultra-secure communication networks, advanced sensing technologies, and the future of quantum computing.
Quantum teleportation may sound like something out of Star Trek, but it’s grounded in real physics. The process involves transferring the quantum state of one particle to another — not by moving the particle itself, but by entangling it with another and sending the quantum information, effectively recreating the state at a distant location. This delicate process still requires a classical signal to link the two ends of the transmission.
The challenge lies in preserving these fragile quantum states, which are notoriously susceptible to interference. Much like cotton candy dissolving in the rain, quantum information can quickly degrade when exposed to environmental noise — especially when traveling alongside traditional internet traffic.
“This is incredibly exciting because nobody thought it was possible,” said Prem Kumar, the lead researcher and a computing engineer at Northwestern University. “Our work shows a pathway toward integrated quantum and classical communication networks using existing fiber optics.”
To accomplish this feat, the team developed methods to protect the quantum signal — a single photon — from being scattered or disrupted as it traveled through busy internet lines transmitting up to 400 gigabits per second. By carefully choosing the photon’s wavelength and optimizing its channel, the team minimized interference from the classical data flow.
“We studied how light is scattered and positioned our photons at a point where that scattering is minimized,” explained Kumar. “We found that quantum communication could happen without interference from the classical channels.”
Although other experiments have simulated quantum data sharing alongside classical signals, this is the first successful demonstration of quantum teleportation using an active, real-world internet stream.
The success hints at a future where quantum communication can scale without the need for entirely new infrastructure. With proper calibration of wavelengths, existing internet cables could support both traditional and quantum data, making a global quantum network more feasible than ever.
“Quantum teleportation allows for secure connections between far-apart nodes,” said Kumar. “And contrary to what many believed, we may not need specialized infrastructure to make this a reality. Classical and quantum communications can indeed coexist.”
The findings were published in the journal Optica.