Raise your hand if you ever wanted to get beamed onto the transport deck of the USS Enterprise. Maybe we haven’t reached the point of teleporting entire human beings yet (sorry Scotty), but what we have achieved is a huge breakthrough towards quantum internet.
Led by Caltech, a collaborative team from Fermilab, NASA’s Jet Propulsion Lab, Harvard University, the University of Calgary and AT&T have now successfully teleported qubits (basic units of quantum info) across almost 14 miles of fiber optic cables with 90 percent precision. This is because of quantum entanglement, the phenomenon in which quantum particles which are mysteriously “entangled” behave exactly the same even when far away from each other.
When quantum internet is finally a thing, it will make Wifi look obsolete and dial-up even more ancient than it already is. “We achieved sustained, high-fidelity quantum teleportation utilizing time-bin (time-of-arrival_ qubits of light, at the telecommunication wavelength of 1.5 microns, over fiber optic cables,” Panagiotis Spentzouris, Head of Quantum Science at the Fermilab Quantum Institute, told SYFY WIRE. “This type of qubit is compatible with several devices that are required for the deployment of quantum networks.”
What you might recognize is the fiber optic cables used in the experiment, since they are everywhere in telecommunication tech today. Lasers, electronics and optical equipment which were also used for the experiments at Caltech (CQNET) and Fermilab (FQNET) that could someday evolve into the next iteration of internet. Though this is equipment you probably also recognize, what it did for these experiments was enable them to go off without a glitch. Information traveled across the cables at warp speed with the help of semi-autonomous systems that monitored it while while managing control and synchronization of the entangled particles. The system could run for up to a week without human intervention.
So if entangled qubits are inextricably linked despite the distance between them, is there even a limit to how far information can travel? Hypothetically, they could go on forever. What limits exist in reality are not in the qubits but the effects of their surroundings. While one of the qubits containing information stays where it is, the other one has to zoom over to wherever it needs to transfer that information. It could run into obstacles on the way.
“What limits the distance that information can be transmitted is loss and noise: either from the properties of the medium we use to send the information or the effects of the environment on the medium, or imperfections on the various operations we need to perform to realize the information transfer,” Spentzouris, who coauthored a study recently published in PRX Qunatum, said.
To keep quantum internet running at high precision and over distances around what it was able to cover in this experiment, the quantum teleportation that powers it needs quantum memory and quantum repeaters. Quantum memory is basically the quantum version of the memory your computer and smartphone use now. Instead of storing memory as something like 100101011, it stores it in the form of qubits. To make it possible for entangled qubits to travel as far as possible, quantum repeaters make it easier for those qubits to traverse by splitting it into sections over which they are teleported.
With this system, Spentzouris and his team are planning to lay out the epic Illinois Express Quantum Network (IEQNET), which will use the same technologies that the CQNET and FQNET experiments so successfully pulled off. More tech will obviously needed to realize this sci-fi brainchild. It will combine quantum and non-quantum functions for its quantum nodes and controls. The only thing missing will be the repeaters, since they will need more development to operate over such an expanse. Spentzouris believes quantum computing itself reaches far beyond internet.
“Fully distributed quantum computing includes applications include GPS, secure computation beyond anything that can be achieved now, all the way to enabling advances in designing new materials and medicine, as well basic science discoveries,” he said. “It will unleash the full power of quantum computing and have a profound impact on our lives.”