In a first, researchers in China have teleported a photon from Earth to a satellite in orbit, 311 miles away. Since the 1990s, scientists have routinely teleported quantum particles in a laboratory setting, and last year, scientists completed the first ever quantum teleportation outside of a lab.
This time, the photon traveled into Earth’s orbit, arriving at a satellite called Micius, a highly sensitive photo receiver that can detect the states of individual photons fired from the ground. It was launched in order to test the components for quantum feats such as entanglement, cryptography, and teleportation. The recent teleportation was one of the first results of these planned experiments.
The Chinese research team told MIT Technology Review:
“Long-distance teleportation has been recognized as a fundamental element in protocols such as large-scale quantum networks and distributed quantum computation. Previous teleportation experiments between distant locations were limited to a distance on the order of 100 kilometers, due to photon loss in optical fibers or terrestrial free-space channels.”
Quantum teleportation differs from the teleportation common in science fiction. Quantum teleportation builds on the phenomenon of quantum entanglement, in which quantum particles form at the same instant and point in space, sharing an existence that continues to be shared even when the particles are separated. This means a measurement on one of the particles immediately has an effect on the other, no matter the distance between them.
The connection can be used to share quantum information, transmitting the information from one photon over the link to another entangled photon, which takes on the identity of the original particle.
For this experiment, the researchers created pairs of entangled photons, at a rate of roughly 4,000 a second. They transmitted one of the photons to the satellite, while the other remained on the ground. The team then measured the photon on the ground as well as the one in orbit to confirm the entanglement.
Notably, telporation of any larger objects still won’t be a possibility anytime soon. And even though there’s no maximum distance for the link, it can easily break down. However, the experiment opens the door to further studies of quantum teleportation.
This work establishes the first ground-to-satellite up-link for faithful and ultra-long-distance quantum teleportation, an essential step toward global-scale quantum internet,” according to the research team.