Quantum light is like an ocean

Scientists at the University of Calgary said they’ve manipulated a quantum property of light called entanglement and built two-story quantum “toy houses” of any style and architecture.

The researchers focused a blue laser onto a specialised crystal using mirrors and lenses. The crystal, they said, takes high energy blue photos and turns them into a quantum superposition of low energy red photons, coming out in two directions.

The photons are “entangled” – any measurement in one channel causes an immediate change in the other channel.  This, apparently, is “quantum weirdness” and described by Albert Einstein as “spooky action at a distance”.

So what’s it all for? According to the author of the paper, Alexander Lyvovsky, a professor in U of C’s department of physics and astronomy: “Light is a particularly interesting quantum object because it’s an excellent communication tool. No matter what future quantum computers will be made of, they’ll talk to each other using photons.”

Manipulating quantum objects will potentially open up very sensitive measurement instruments, far faster computers, secure comms systems and better control over chemical reacions.

And Lyvovsky waxed lyrical about quantum light itself. “[It’s] like an ocean, and it’s full of mysteries and treasures. Our task is to conquer it. But so far, physicists were able to control only a tiny island in this ocean. What we have done is to make this island bigger.” The research is published in Nature Photonics.