Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Finding solid ground

21.02.2011
Experimental evidence adds to the likelihood of the existence of supersolids, an exotic phase of matter

Supersolids and superfluids rank among the most exotic of quantum mechanical phenomena. Superfluids can flow without any viscosity, and experience no friction as they flow along the walls of a container, because their atoms ‘condense’ into a highly coherent state of matter. Supersolids are also characterized by coherent effects, but between vacancies in a crystal lattice rather than between the solid’s atoms themselves.

The reduction in the rotational inertia of a bar of solid helium-4 as it was cooled to very low temperatures provided the first experimental evidence for supersolids. Physicists interpreted the reduction to mean that some amount of supersolid helium had formed and decoupled from the remainder of the bar, affecting its rotational inertia and frequency. Others argued that the reduction in inertia resulted from a change in the helium’s viscosity and elasticity with temperature, rather than from the onset of supersolidity.

Kimitoshi Kono from the RIKEN Advanced Science Institute in Wako, Eunseong Kim from KAIST in Korea, and their colleagues from these institutes have now disproved the alternative interpretation by simultaneously measuring the shear modulus (a measure of viscosity and elasticity) and the rotational inertia of a solid helium-4 cell as its temperature dropped from 1 kelvin to 15 thousandths of a kelvin[1]. The cell was made to rotate clockwise and then counterclockwise periodically, as well as to rotate clockwise or counterclockwise continuously (Fig. 1). The continuous rotation affected the inertial mass of the helium but its shear modulus, allowing these quantities to be monitored independently.

Under continuous rotation, the degree of change in the rotational inertia had a clear dependence on rotation velocity, while the shear modulus did not. In addition, the energy dissipated by the rotation increased at high speeds. Both of these observations contrast to what would be expected if viscoelastic effects were at play, rather than supersolidity. The researchers also found that periodic rotation and continuous rotation affected the rotation differently, raising new questions about the experimental system.

The data support the interpretation that changes in the rotational inertia of helium-4 at low temperature result from supersolidity. This is important because of the novel and surprising nature of the phenomenon itself, says Kono. “Superfluidity in a solid is a very radical concept which, if proven, is certainly a good candidate for the Nobel Prize” he adds. “Therefore the first priority is to determine whether it can be proven in a fashion that will convince the low-temperature physics community.”

The corresponding author for this highlight is based at the Low Temperature Physics Laboratory, RIKEN Advanced Science Institute

Journal information

[1] Choi, H., Takahashi, D., Kono, K. & Kim, E. Evidence of supersolidity in rotating solid helium. Science 330, 1512–1515 (2010).

gro-pr | Research asia research news
Further information:
http://www.riken.jp
http://www.researchsea.com

More articles from Physics and Astronomy:

nachricht From rocks in Colorado, evidence of a 'chaotic solar system'
23.02.2017 | University of Wisconsin-Madison

nachricht Prediction: More gas-giants will be found orbiting Sun-like stars
22.02.2017 | Carnegie Institution for Science

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Breakthrough with a chain of gold atoms

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

Im Focus: DNA repair: a new letter in the cell alphabet

Results reveal how discoveries may be hidden in scientific “blind spots”

Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...

Im Focus: Dresdner scientists print tomorrow’s world

The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.

The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...

Im Focus: Mimicking nature's cellular architectures via 3-D printing

Research offers new level of control over the structure of 3-D printed materials

Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...

Im Focus: Three Magnetic States for Each Hole

Nanometer-scale magnetic perforated grids could create new possibilities for computing. Together with international colleagues, scientists from the Helmholtz Zentrum Dresden-Rossendorf (HZDR) have shown how a cobalt grid can be reliably programmed at room temperature. In addition they discovered that for every hole ("antidot") three magnetic states can be configured. The results have been published in the journal "Scientific Reports".

Physicist Dr. Rantej Bali from the HZDR, together with scientists from Singapore and Australia, designed a special grid structure in a thin layer of cobalt in...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Booth and panel discussion – The Lindau Nobel Laureate Meetings at the AAAS 2017 Annual Meeting

13.02.2017 | Event News

Complex Loading versus Hidden Reserves

10.02.2017 | Event News

International Conference on Crystal Growth in Freiburg

09.02.2017 | Event News

 
Latest News

Stingless bees have their nests protected by soldiers

24.02.2017 | Life Sciences

New risk factors for anxiety disorders

24.02.2017 | Life Sciences

MWC 2017: 5G Capital Berlin

24.02.2017 | Trade Fair News

VideoLinks
B2B-VideoLinks
More VideoLinks >>>