Scientists Teleported Quantum Data over 60 Miles
Moving information from one place to another currently means it has to actually cover the distance in between, but that might not always be the case. Scientists have been working on technologies that enable quantum teleportation of data, and they’ve just smashed the previous record by teleporting bits across 60 miles of fiber cable. This is a four-fold improvement over the previous record.
When we talk about quantum teleportation, we’re not talking about matter transfer, at least not yet. You could say everything is information at some level, but this is more a case of remotely reconstructing data that’s held in a quantum state. The result is the same, though. The data was in one place, then in the blink of an eye it’s someplace else without being transmitted directly. This latest breakthrough happened at the National Institute of Standards and Technology (NIST), but it wasn’t really a usable amount of data. The team transferred the quantum state of one photon to another at the opposite end of a 60-mile spool of fiber optic cable.
The NIST researchers were able to push quantum teleportation so far thanks to the development of a new single-photon detector. Like past experiments in quantum teleportation, we’re still talking about entanglement — here’s how it works with the new detector. A photon is produced, then split with a crystal prism into two identical and entangled photons. One photon is sent to the end of the cable, making it the output. Meanwhile, the other entangled photon is passed into a beam splitter with a new photon, which is the input. These two beams are randomly either in-phase or out of phase — this is the data you’re trying to teleport.
There are fancy new detectors at the output end of the fiber and at the beam splitter. The detector pings each time a photon hits it, allowing the team to determine if the photons are in-phase or out-of-phase at the input. Sure enough, at the output end, the detector data matched the input. Check the image below for a more visual explainer. That means the quantum data was transported from one end to the other. The signal is very weak, though. Only 1 percent of photons make it all the way through the cable to be read, so this experiment wouldn’t have been possible without the new detectors.
This is clearly a long way from a true communication medium, but it gets us closer to the possibility of quantum encryption. You’d never have to worry about your communications being intercepted with quantum encryption, because its very existence is obscured by quantum states. It could also make quantum computing a more viable technology. Maybe one day, we’ll be able to move more than photon states, but there’s still more work to be done before you’ll get to beam yourself up.
source: extremetech
