The metallic alloy, which, when cooled below a specific threshold temperature, the material dramatically loses all electrical resistance, is known as a superconductor. In principle, superconductors can allow electrical current to flow without any energy loss. It is known as supercurrent.
Recent research suggests a new explanation for how superconductors exposed to a magnetic field can recover to their previous state after the magnetic field vanishes without loss of energy. This research made at the University of Tsukuba opened a way to a new theory of superconductivity. It may also lead to an eco-friendly electrical distribution system.
Superconductors allow the electricity to flow with zero resistance to current. The current circle around the superconducting wore indefinitely in a loop. The temperature is the catch here. These materials must be kept very cold, and even so, a strong magnetic field can cause a superconductor to revert to normal.
In the past, the thought was that the superconducting-to-normal transition caused by a magnetic field is difficult to reverse. Since the usual process of Joule heating would dissipate the energy, this mechanism, by which the resistance in regular wires converts electrical energy into heat, is what allows us to use an electric stovetop or space heater.
Professor Hiroyasu Koizumi of the Division of Quantum Condensed Matter Physics, Explains:
“Joule heating is usually considered negative because it wastes energy and can even cause overloaded wires to melt. However, the imagination from experiments was that, if you remove the magnetic field, a current-carrying superconductor can return to its previous state without loss of energy,”
“In the superconducting state, electrons pair up and move in sync. Still, the real cause of this synchronized motion is the presence of the so-called “Berry connection.” It is an integer and if it is nonzero current flows. Thus, this supercurrent can be switched off abruptly by changing this number to zero without Joule heating”.
“The surprising thing is that a model from the early days of electromagnetism, like Maxwell’s idle wheels, can help us resolve questions arising today. This research may help lead to a future in which energy can deliver from power plants to homes with perfect efficiency.”