An international team of researchers from Russia, Spain, Belgium, the U.K. and the U.S. Department of Energy’s (DOE) Argonne National Laboratory has discovered groundbreaking applications of superconductivity. The study appeared in Nature Communications last week.
They were able to establish how to stabilize efficiently tiny magnetic vortices, which interfere with superconductivity. This problem has been unable to get solved for decades. Such an incredible finding can clear the way to numerous advances and developments in superconductor technology.
Superconductors minimize the loss of electricity during transport, regardless of whether the distance electricity travels is from an outlet to an electrical appliance, or from a power plant to a consumer located miles away from the source.
One of the greatest limitations of superconductors, however, is the fact that they need to be cooled down to -280° Fahrenheit, which leads to numerous engineering and logistical problems.
This is also the reason why scientists are working towards creating a superconductor that could work at room temperatures, although to achieve this aim, they will first need to solve problems that are apparent even in low-temperature environment.
Magnetic fields pose one of these problems. They have the ability to make a superconductor lose its superconductivity when the reach certain strength.
Scientists have already developed the type of superconductor– “Type II”. It can survive high magnetic fields because of the so-called ‘vortices’ that are formed inside the superconductor. Eventually these vortices begin to move and interfere with the superconductivity of the material, introducing resistance.
According to Argonne Distinguished Fellow Valerii Vinokur, who co-authored the study, the only solution to this problem would be to find a way to pin the vortices and stop them from moving under applied currents.
Studies over the past couple of decades have looked into various methods that could restrain these vortices, but the success has been minimal, until now.
The study conducted by Vinokur and his colleagues used thin superconducting wires, which could accommodate only one row of vortices. When high magnetic field was introduced, the scientists observed that the vortices crowded together in long clusters and became immobilized, which restored the superconductivity of the material instead of destroying it.
In the following stage on the experiment, the team carved superconducting film into an array of holes. This allowed only a limited number of vortices to move to the holes, where they became fixed and unable to interfere with the current.
According to Vinokur, the resistance of the superconductor was thus decreased dramatically. No other study has been able to pin the vortices at such temperatures and magnetic field before. Although the experiment has been tested only at very low temperatures, the scientists are convinced that it should work at higher temperatures too.