The behavior of intermetallic superconductors, like the kind used in hospital MRI machines, is even more curious than recent Nobel Prize-winning physicist Alexei Abrikosov had theorized. In newly reported research,* scientists working at the National Institute of Standards and Technology (NIST) Center for Neutron Research have determined that so-called type II superconductors have the equivalent of a multiple personality---at least three distinct physical states, each with its own superconducting behavior. The result should help engineers design new materials for stronger, more efficient superconducting magnets.
Nearly 50 years ago, Abrikosov predicted that superconductors could retain superconductivity in a very strong magnetic field by forming tiny eddies of current. These vortices allow the field to pass through without disrupting the current, until a certain threshold is reached and the resistance-free flow of electrons ceases. Just before the collapse, however, the materials undergo a dramatic spike in current, called the peak effect.
Over a wide range of temperatures and magnetic field strengths, Brown University and NIST scientists tracked the movements of current eddies in a prototype type II superconductor, niobium. Their experiments yielded a phase diagram, a kind of a map that shows how current vortices rearrange in response to changes in temperature and magnetic field.
Mark Bello | EurekAlert!
Innovative genetic tests for children with developmental disorders and epilepsy
11.07.2018 | Christian-Albrechts-Universität zu Kiel
Oxygen loss in the coastal Baltic Sea is “unprecedentedly severe”
05.07.2018 | European Geosciences Union
A new manufacturing technique uses a process similar to newspaper printing to form smoother and more flexible metals for making ultrafast electronic devices.
The low-cost process, developed by Purdue University researchers, combines tools already used in industry for manufacturing metals on a large scale, but uses...
For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.
To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...
For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.
Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...
Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.
A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...
Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.
"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....
13.07.2018 | Event News
12.07.2018 | Event News
03.07.2018 | Event News
20.07.2018 | Power and Electrical Engineering
20.07.2018 | Information Technology
20.07.2018 | Materials Sciences