Photons disappear. That is one of the central problems in quantum communication. As particles of light travel over long distances, they scatter, get absorbed, or simply vanish. The farther they go, the worse the loss becomes. Now, researchers in China say they have demonstrated a way around the problem.
Scientists at the University of Science and Technology of China compared quantum teleportation directly against standard photon transmission and found that teleportation delivered a quantum signal more efficiently over a lossy channel. Their findings were published in Nature Physics.
According to a report by Phys.org, quantum teleportation does not move a particle from one place to another. Instead, it transfers a quantum state between particles through a phenomenon called quantum entanglement. The particle carrying the information never has to travel the full distance of the channel, which is where so much of the loss normally happens.
The research team introduced a new method to prepare entangled photons remotely, which made the teleportation process more practical over real-world distances. The key challenge with teleportation has always been that it only works well when the entanglement between distant nodes is established effectively.
Chaoyang Lu, co-senior author of the paper, told Phys.org that the field has moved past simply showing that quantum effects exist. "In quantum information science, we have reached a stage where a central goal is no longer simply to demonstrate fascinating quantum effects, but to show that quantum technologies can outperform the best classical alternatives in well-defined tasks," Lu said. "Such demonstrations are key milestones on the road toward practical quantum information technologies."
Lu pointed to earlier work from his group as context. "A good example from our own work is Jiuzhang, the photonic quantum computer we demonstrated in 2020, which showed quantum computational advantage using photons," he said.
His team had spent years pushing teleportation into more complex territory. "Over the years, our group has explored teleportation in increasingly complex systems, including multiple degrees of freedom and high-dimensional quantum states," Lu said. "After these proof-of-principle experiments, we began to ask a very simple question: in a real experiment, can teleportation transmit a photonic qubit more efficiently than simply sending the photon directly through the same lossy channel?"
The answer, based on their results, is yes. What makes the finding significant is not just that teleportation worked, but that no previous study had run a direct experimental comparison between the two methods. Researchers had explored teleportation for more than four decades without ever setting it head to head against direct transmission under equivalent conditions.
The paper positions quantum teleportation as a viable and potentially superior method for building long-distance quantum communication networks, where photon loss has been a persistent barrier to practical deployment.
