A spiral through frozen heliumS

What you're seeing here is a spiral created by a special state of matter called supersolidity. All it takes is freezing cold helium and a few other helium atoms intrepid enough to crawl through it. Put them together and you can make an incredible pattern.

This spiral is a crystal of silicon carbide, made during an experiment conducted in 2007. The experiment required a special state of helium. At first, the helium was frozen solid ā€” quite a feat, since helium is a gas at room temperature. Once it solidified, it forms a kind of crystal, but not a perfect one. There are flaws in the crystal, and, when the mixture reached a certain temperature and pressure, the solid helium turned to a superfluid.

A superfluid is an utterly frictionless fluid. We think of fluids as flowing with movement, but in this experiment the superfluid did the opposite. The crystal of frozen helium was twisted around, and suddenly the twisting got easier, as if some of the mass had disappeared. Due to superfluidity, some of it effectively had. Because there was no friction to push the liquid, it stayed still, slipping through the flaws in the crystal, while the rest of the crystal moved around it, forming a spiral. The combination formed what researchers call a supersolid.

Image: Institute for Crystal Growth, Germany

Via: APS, Physics