- Number 421 |
- September 1, 2014
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ORNL scientists uncover clues to role of magnetism in iron-based superconductors
New measurements of atomic-scale magnetic behavior in iron-based superconductors by researchers at the Department of Energy’s Oak Ridge National Laboratory and Vanderbilt University are challenging conventional wisdom about superconductivity and magnetism.
The study published in Advanced Materials provides experimental evidence that local magnetic fluctuations can influence the performance of iron-based superconductors, which transmit electric current without resistance at relatively high temperatures. -
Finding fingerprints of selection in poplars
Since the publication of the poplar genome by the U.S. Department of Energy Joint Genome Institute (DOE JGI) in 2006, it has been used to understand woody perennial plant development and served as a model for genome-level insights in forest trees. In a recent study published online August 24, 2014 in Nature Genetics, a team led by Gerald Tuskan of Oak Ridge National Laboratory (ORNL) and the DOE JGI – a DOE Office of Science user facility – and Stephen DiFazio of West Virginia University used a combination of genome-wide selection scans and analyses to understand the processes involved in shaping the genetic variation of natural poplar (Populus trichocarpa) populations.
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NREL unlocking secrets of new solar material
A new solar material that has the same crystal structure as a mineral first found in the Ural Mountains in 1839 is shooting up the efficiency charts faster than almost anything researchers have seen before—and it is generating optimism that a less expensive way of using sunlight to generate electricity may be in our planet's future.
Researchers at DOE's National Renewable Energy Laboratory (NREL) are analyzing the new material, perovskite, using the lab's unique testing capabilities and broad spectrum of expertise to uncover the secrets and potential of the semiconducting cube-like mineral. -
Chromium's bonding angles let oxygen move quickly
By taking advantage of the natural tendency of chromium atoms to avoid certain bonding environments, scientists at DOE’s Pacific Northwest National Laboratory have generated a material that allows oxygen to move through it very efficiently, and at relatively low temperatures. Specifically, they found that their attempts to make metallic SrCrO3 lead instead to the formation of semiconducting SrCrO2.8. Because chromium as an ion with a charge of +4 does not like to form 90º bonds with oxygen, as it must in SrCrO3, SrCrO2.8 forms instead with a completely different crystal structure. This material contains oxygen-deficient planes through which oxygen can diffuse very easily.
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Grad student's astrophysical insights could apply to fusion
Graduate student Jonathan Squire has won a highly competitive Honorific Fellowship from the Princeton University Graduate School. The award, for which Squire was nominated by the Princeton Program in Plasma Physics at DOE's Princeton Plasma Physics Laboratory, recognizes outstanding performance and professional promise and provides tuition and a stipend to fellowship winners.
Squire is developing a new theoretical insight into the growth of magnetorotational instability, a subtle process that appears to control the flow of matter around black holes and has implications for the creation of celestial bodies. The process takes place when matter in the form of magnetized plasma rotates around celestial objects and is drawn into them when the rotation grows unstable. “This is an astrophysical issue but our methods of approaching the problem could also prove very useful in fusion research,” said Squire.