Scientists just smashed the distance record for quantum tele
Source: Rachel Feltman
Physicists at the National Institute of Standards and Technology (NIST) have broken the quantum teleportation record in a big way. In a paper published this week in Optica, they report successfully transferring information from one photon to another across over 60 miles of fiber-optic cable -- four times the distance of the previous record.
What's all that mean? Most of us hear the word "teleportation" and think of "Star Trek," but quantum teleportation is very real -- and slightly less exciting.
It relies on something called quantum entanglement -- what Albert Einstein called "spooky action at a distance." When close subatomic particles become entangled, they become linked forever -- even if they're taken very far apart from each other. When one of those particles transmits its quantum data to the other, it's essentially teleporting itself.
To break the distance record, the NIST had to use a very sensitive detector, one that could detect single photons. "Only about 1 percent of photons make it all the way through 100 km of fiber," NIST's Marty Stevens said in a statement. "We never could have done this experiment without these new detectors, which can measure this incredibly weak signal."
Why bother with sending bits of light back and forth? Unfortunately for us sci-fi nerds, messing around with quantum teleportation isn't about working our way up to real teleportation. Instead, the ultimate goal most people talk about is something called quantum encryption. Here's a description from Physics World:
Quantum cryptography involves two parties sharing a secret key that is created using the states of quantum particles such as photons. The communicating parties can then exchange messages by conventional means, in principle with complete security, by encrypting them using the secret key. Any eavesdropper trying to intercept the key automatically reveals their presence by destroying the quantum states.
In theory, it would be impossible to hack information encrypted using this method. It goes without saying that plenty of people are very interested in making that happen.
But first we're going to need quantum teleportation to work more reliably -- and at longer distances. The NIST team is working on creating more sensitive detectors to push those limits.
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