And we can now produce it using a mechanical object.
To work, quantum computers have to be freezing cold, which makes connecting them to one another a challenge.
Now, for the first time, a team of researchers has found a way to create entangled radiation using a physical object — a move that could help connect future quantum computer systems to the outside world.
"What we have built is a prototype for a quantum link," Shabir Barzanjeh, the engineer who led the project, said in a press release. "The oscillator that we have built has brought us one step closer to a quantum internet."
According to the research, which was published Wednesday in the journal Nature, the Institute of Science and Technology Austria scientists produced entangled radiation using a 30-micrometer-long piece of silicon.
That's small for practical purposes — an average hair is 50 micrometers long — but huge compared to the scale of quantum experiments.
Eventually, this radiation could be used to send information between future quantum computers and external data centers, similarly to how classical computer networks use light radiation to send information along fiber optic cables, according to the press release.
READ MORE: Building a bridge to the quantum world [IST Austria]
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