Scientists have spent the entirety of human history coming up with a series of zany and amazing ideas – most of which fall by the wayside. Over time, as we developed writing and education, more and more stories were written by people with little or no scientific grounding – increasing the pool of ‘blue sky concepts’ by a huge amount. Then, every now and then, one of these flights of fancy comes home to roost. KitGuru dons a dark hood and asks if these are the photons we have been looking for.
Remember the first time you played with ‘proper glue’? Maybe it was when you made a model plane or needed to stick 2 pieces of paper together and the baby-glue-stick wasn’t available. A little while later, you had covered everything in the gunky substance and were fascinated by the smell and rubbing it off your fingers.
Did you imagine it might be possible to glue photons of light together?
We know through Einstein and atomic bombs that physical mass can be converted to energy and an enormous amount of light, but we don’t tend to think of the opposite happening.
Now, a team of scientists at Harvard University (the place where they also discovered Facebook), led by Mikhail Lukin, have made an amazing discovery.
In the right conditions, they have proven that it is possible to glue two photons together.
Shine lasers at each other and nothing happens – the two beams simply pass through each other with zero interaction. The Harvard researchers sent single photons into a super-cooled chamber filled with a cloud of rubidium atoms. The idea is to get the photon to slow down.
So far, all well and good, but when they tried the same experiment with 2 photons – they were able to get them to combine and exit as a single ‘molecule’. In effect, the two photons have been glued together.
Lukin explained the principal, “It’s the same effect we see with refraction of light in a water glass. The light enters the water, it hands off part of its energy to the medium, and inside it exists as light and matter coupled together, but when it exits, it’s still light. The process that takes place is the same it’s just a bit more extreme – the light is slowed considerably, and a lot more energy is given away than during refraction. The two photons push and pull each other through the cloud as their energy is handed off from one atom to the next. It’s a photonic interaction that’s mediated by the atomic interaction. That makes these two photons behave like a molecule, and when they exit the medium they’re much more likely to do so together than as single photons”.
When the reaction occurs, it apparently creates a visual effect similar to staring down a lightsabre, but the real world applications are more likely to come in the field of quantum computing.
KitGuru says: While Lukin cannot hope to rival the impact that Harvard’s Facebook has had on human culture, it would be nice to have lightsabres and holodecks that work.
Comment below, in the KitGuru forums or join us online over at Facebook.