The latest advance toward understanding the electron transport mechanism of high-temperature superconductors, as reported in the June 3 issue of the British journal Nature, relies on materials provided by Dr. Fatih Dogan, a professor of ceramic engineering at UMR.
The paper, "The structure of the high-energy spin excitations in a high-transition temperature superconductor," by Dr. S.M. Hayden of the University of Bristol in the United Kingdom, Dogan, and a group of other researchers, brings science a step closer to finding the "missing link" between the creation of novel superconductors with higher transition temperature and their electronic structure, says Dogan. High-temperature superconductors are ceramic materials that carry electric current — with no loss of energy — at relatively higher temperatures using liquid nitrogen instead of liquid helium. Discovery of new materials, which would become superconducting at room temperature or higher, would be revolutionary. But the mechanism that makes them work is still not understood, says Dogan.
Dogan and his colleagues have been researching this for 10 years. "With each step we make progress, but the mechanism of high-temperature superconductivity is so complex," says Dogan. The group will continue the research until the mechanism is discovered, either by them or someone else in the field.
Dogan uses novel techniques to process yttrium barium copper oxide materials, which are investigated by neutron scattering experiments. He forms the elements into a single crystal that is tailored for measurements using neutrons. His colleagues then use the measurements as a tool to understand the electronic structure of superconducting materials. "The microstructural development of the single crystals is very crucial to neutron scattering experiments and requires a clear understanding of solidification processes of complex material systems through nanoscale science and engineering," says Dogan.
"If the mechanism, of theory, of high-temperature superconductivity is revealed we might be able to formulate many other new materials with superconducting properties," he says. "Any material discovered that has the higher transition temperature would be important for mankind. It would change the current technology completely. For example, extremely fast computers would be based on superconducting materials, and there would be no heat management problems in electronic circuitry, because heat is generated by the resistivity and superconductors have no resistivity.
"It would definitely help the environment; we would save a lot of energy in power lines and all electronic devices we have. It would be a new revolution in technology if those materials can be discovered and processed easily," says Dogan.
Besides Hayden and Dogan, other members of the research group include Dr. H.A. Mook of Oak Ridge National Laboratory; Dr. Pengcheng Dai of Oak Ridge National Laboratory and the University of Tennessee; and Dr. T. G. Perring of the Rutherford Appleton Laboratory, United Kingdom.