Published on September 6th, 2012 | by James Ayre0
Researching Magnetism to Understand Superconductivity
September 6th, 2012 by James Ayre
The electrical resistance that occurs in power lines adds up to energy losses of nearly 3% of an electrical grid’s total. On the scale of a country, this equals several thousand lost gigawatt-hours. In the case of a country like Switzerland, it’s the equivalent of the electricity consumption of a large city like Geneva.
The possibility of transferring electricity without any of this loss of current has long been a goal of energy researchers. And it appears that now that may finally be within grasp, thanks to new research into the behavior of magnetism at extremely small scales.
“Materials known as ‘high temperature’ superconductors (even though they must be maintained at -140°C!), which can conduct electricity without any losses, were supposed to make this dream a reality. But over the past twenty-five years, scientists have not been able to make any progress in this area. Research being done in EPFL’s Laboratory for Quantum Magnetism (LQM) could change that. Their study of magnetism at extremely small scales could give physicists a tool to use in their search for new superconducting materials.”
Some forms of ceramics make very good insulators at room temperature, but when submersed in liquid nitrogen become perfect conductors. This behavior, named “high temperature” superconductivity, is not well understood by physicists. But it’s been theorized that, when at these low temperatures, “the collective quantum magnetic properties of the atoms in the material might come into play.”
For the new research, a new and unique device was created by the researchers to help improve our understanding of the phenomenon. The research team created a layer just a single atom thick, and then used an ultrasensitive instrument to measure the magnetic dynamics of the atoms. “And then EPFL provided the final piece of the puzzle, with mathematical models to analyze the measurements.”
“We now have a kind of flashlight that will show us what direction we should take in our search,” explains Ronnow. “Without understanding how these superconducting properties occurred at these temperatures, researchers were probing in the dark, using trial and error, to explore promising new materials. By combining these results with other recent work done by LQM researcher Nikolai Tsyrulin, the EPFL team has provided a new method to help physicists in their search for new superconductors.”
Source: Ecole Polytechnique Fédérale de Lausanne
Image Credits: DOE/Ames Laboratory