Shaking down frozen helium: In a 'supersolid' state, it has liquid-like characteristics

May 12, 2011

In a four-decade, Holy Grail-like quest to fully understand what it means to be in a "supersolid" state, physicists have found that supersolid isn't always super solid. In other words, this exotic state of frozen helium appears to have liquid-like properties, says a new paper published in the journal Science on May 13, 2011.

Why is this important? Understanding helium brings us closer to understanding its close cousins superconductivity and superfluidity.

Physicists had long thought that the unusual behavior of torsion oscillators containing solid helium meant that chilling helium down to temperatures near prompts its transformation into a supersolid. It is certainly solid, but in this physical quest, there was a nagging question: Is it a true supersolid?

To gain new perspectives on solid helium, new research tools were needed. "Think of this analogy: when Galileo first peered through a telescope, he saw ears on . With improved technology, humanity began to understand those ears were actually rings around the planet. And with better technology, we saw the differences in the rings. To further understand solid helium, science had to invent new approaches," says Séamus Davis, Cornell professor of physics. "Helium is a pure material. We're gaining a new understanding of the fundamental issues of how nature works, of how the universe works."

In fact, in this paper, the researchers show instead a more prosaic explanation: There are moving defects in the solid helium crystals, and their relaxation time falls with rising temperatures. This is more consistent with the torsional oscillation (shaking) experiments conducted at Cornell.

The researchers learned that the unusual properties of solid do not reflect a clunky transition between the solid state and a supersolid state. It behaves like a dimmer switch and presents a smooth transition near absolute zero.

Explore further: Unexpected new mechanism reveals how molecules become trapped in ice

More information: "Interplay of Rotational, Relaxational, and Shear Dynamics in Solid 4He," Science (May 13, 2011).

Related Stories

A crack in the case for supersolids

Jun 21, 2010

New experiments are casting doubt on previously reported observations of supersolid helium. In a paper appearing in the current issue of Physical Review Letters, John Reppy (Cornell University) presents research suggesting that p ...

Probable observation of a supersolid helium phase

Apr 21, 2004

Just last year we have seen a Nobel Prize in physics awarded to Abrikosov, Ginzburg and Leggett for "pioneering contributions to the theory of superconductors and superfluids" And now Nature publishes an article by E. Kim ...

Frozen helium-4 may be an unusual 'superglass'

May 01, 2009

(PhysOrg.com) -- When helium is cooled to around 4 degrees above absolute zero, it turns liquid. Make it a couple of degrees cooler, and it becomes a "superfluid" that flows without resistance from its container, ...

Recommended for you

'Pixel' engineered electronics have growth potential

Sep 29, 2014

(Phys.org) —A little change in temperature makes a big difference for growing a new generation of hybrid atomic-layer structures, according to scientists at Rice University, Oak Ridge National Laboratory, ...

2-D materials' crystalline defects key to new properties

Sep 24, 2014

Understanding how atoms "glide" and "climb" on the surface of 2D crystals like tungsten disulphide may pave the way for researchers to develop materials with unusual or unique characteristics, according to an international ...

User comments : 1

Adjust slider to filter visible comments by rank

Display comments: newest first

orgon
not rated yet May 15, 2011
This effect is of the same ballistic transport mechanism, like the "tin cry" effect and/or fresh snow crackling & crunching beneath your feets.

http://www.period...mple.WAV