Science News Archive

What’s the matter?

Physicists at the University of Pittsburgh have created a new form of matter, which they published in the journal Science this week.  Unfortunately it’s not a form of chocolate that contains zero calories.  The new matter is called a polariton superfluid, which combines the characteristics of laser light with the world’s best electrical superconductors.  To create the new substance, the scientists filled a solid nanoparticle structure with tiny energy particles called polaritons. 

By trapping the polaritons in a tiny “cage”, it slows them down.  This means they come together to act in a co-ordinated way as a single energy wave, rather than a load of particles bouncing about. The wave produces light, similar to laser light, but using much less energy.  The researchers also found that energy moved around from one point to another within the superfluid, similar to the situation seen in superconductors – which are highly efficient electrical conductors.

Normally experiments like this have to be done at extremely low temperatures, because superfluids and superconductors are very unstable.  But the new polariton superfluid seems to be much more stable.  In fact, the lead scientist Professor David Snoke thinks he might be able to create the new matter at room temperature.

At the moment, this is all fairly esoteric physics, but in the future, the technique could be used to transfer light through solid matter.  This might be useful for building super-fast computers, or improving communication technologies.

20th May 2007