Working with colleagues at the Harvard-MIT Center for Ultracold Atoms, a group led by Harvard Professor of Physics Mikhail Lukin and MIT Professor of Physics Vladan Vuletic have managed to coax photons into binding together to form molecules – a state of matter that, until recently, had been purely theoretical. The work is described in a September 25 paper in Nature.
The discovery, Lukin said, runs contrary to decades of accepted wisdom about the nature of light. Photons have long been described as massless particles which don’t interact with each other – shine two laser beams at each other, he said, and they simply pass through one another.
“Photonic molecules,” however, behave less like traditional lasers and more like something you might find in science fiction – the light saber.
“Most of the properties of light we know about originate from the fact that photons are massless, and that they do not interact with each other,” Lukin said. “What we have done is create a special type of medium in which photons interact with each other so strongly that they begin to act as though they have mass, and they bind together to form molecules. This type of photonic bound state has been discussed theoretically for quite a while, but until now it hadn’t been observed.
This is a good follow up about the light saber hype.
A team of physicists from MIT and Harvard have created a new form of matter by binding photons into molecules. The team compared the way these new molecules interact to lightsabers, and the Internet went bonkers. Pump the brakes, everyone. They have not created a lightsaber. Here’s what happened.
Photons don’t interact with each other. If you shine two lasers at one another, the beams can pass through one another completely unaffected. If you try to pass two lightsabers through one another, well, you get Star Wars. The “blades” of the lightsabers do interact by clashing together. They are essentially solid light.
The “photonic molecules” created by the team at the Harvard-MIT Center of Ultracold Atoms interact in a similar way. They don’t simply pass through each other like typical photons. They bump up against each other and clash in a way that can fairly be described as lightsaber-esque if that were a word.
It’s incredible that there’s a new form of matter, and from what we’ve read comparing the interaction of these molecules to lightsabers doesn’t seem like a bad description. Then we saw the headlines that resulted:
No, they didn’t. They created a new form of matter that behaves like a LIGHTSABER.
They have not. Although the photonic molecules interact in a way that compares to lightsabers, that doesn’t mean the molecules are themselves the stuff of lightsabers, or that, even if they were, there is a way to scale that up into an actual working prototype.
Et tu, Wired?
We’d all love to see lightsabers become a reality so we can have our dads chop our hands off and get robot hands, but it’s an unfounded jump to say that photonic molecules equal lightsabers, so please stop doing it. Instead, let’s all focus on the exciting prospects photonic molecules have for quantum computing. …