Scientists stir bizarre ‘supersolid’ matter for first time

PARIS: Scientists on Wednesday said that they have successfully stirred a strange matter called a “supersolid” -- which is both rigid and fluid -- for the first time, providing direct proof of the dual nature of this quantum oddity.

In everyday life, there are four states of matter -- solid, liquid, gas and the rarer plasma.

But physicists have long been investigating what are known as “exotic” states of matter, which are created at incredibly high energy levels or temperatures so cold they approach absolute zero (-273.15 degrees Celsius or -459.67 degrees Fahrenheit).

Under these extreme conditions, matter starts behaving very differently from what we are used to.

Fluids such as liquid or gas may get more or less resistance to flow, which is measured by viscosity. Honey, for example, is more viscous than water.

Superfluids, an extremely cold exotic matter, have zero viscosity -- there is no resistance so they flow freely.

If a superfluid was stirred in a cup, it would flow around indefinitely without ever slowing down.

More than half a century ago, physicists predicted the existence of a “supersolid” state.

It is matter that has the properties of both a solid and a superfluid, in which a fraction of the atoms flow friction-free through the lattice -- a regular arrangement of points or objects -- of a rigid crystal structure.

Researchers had previously managed to observe these crystal structures inside supersolids in several ways.

But a direct observation of the bizarre manner in which this matter flows has remained elusive, said Francesca Ferlaino, a physicist at Austria´s University of Innsbruck.