There is a growing understanding of the conditions required
for superconductivity and how it can be achieved at realistic temperatures
Even physics can give pointers for energy saving. An
international team working together with the Centre for Quantum Materials, run
by the Max Planck Society in conjunction with the University of British
Columbia (Canada), is now in a position to provide materials scientists with
tips for the development of high-temperature superconductors, in a bid to make
them earn their name. The term is currently used to describe materials
including ceramic cuprates, which lose their electrical resistance at significantly
higher temperatures than conventional superconductors, but still well below the
freezing point of water. In two complementary studies, the physicists have now
established that superconductivity in cuprates collapses at a maximum of minus
135 degrees Celsius due to the formation of charge-density waves. These
periodic fluctuations in the distribution of the electrical charges destroy
superconductivity. Consequently, in order to find superconductors that drop to
zero resistance at realistic temperatures, materials scientists must search for
substances that are not subject to charge-density waves.