Higher-temperature superconductivity

Jörg Schmalian, an Iowa State professor of physics and astronomy and an associate of the U.S. Department of Energy's Ames Laboratory, was part of a symposium addressing the 100-year history of superconductivity. The session, "Superconductivity: From 1911 to 2021," took place Feb. 19.

Superconductors are materials that conduct electricity without slowing electrons. For decades, superconductors would only work at temperatures approaching minus 425 degrees Fahrenheit. But advancements have raised that temperature to minus 190 degrees Fahrenheit.

Schmalian's talk, "Superconductivity Without Phonons: From Heavy Electrons to the Cuprates and Pnictides," addressed the microscopic mechanism of those higher-temperature, unconventional superconductors.

Schmalian said electrons in conventional superconductors interact with sound waves to overcome their mutual repulsion to produce frictionless electricity.

"But that doesn't work at higher temperatures," he said. "We have to replace sound waves with something else."

One candidate is magnetism. And a better understanding of how that might work could have implications for MRI scans and other technologies that rely on superconductors.

"We want to understand how we can design and understand these novel materials that will hopefully allow us to increase the temperature where superconducting happens," Schmalian said. "The dream is superconductivity at room temperatures."

Materials science collaborations

Iowa State University will also be mentioned in a symposium describing the Materials Digital Library Pathway, a multi-university collaboration for materials students, teachers and researchers. The collaboration is designed to offer resources that can connect materials research and teaching programs.

Krishna Rajan, an Iowa State professor of materials science and engineering and director of Iowa State's Institute for Combinatorial Discovery, said the idea was to build an Internet repository of data, simulation tools, virtual labs, teaching archives and other materials that could be used by students and teachers. The project was supported by the National Science Foundation and the National Science Digital Library.

"The Materials Digital Library project helped us showcase our work in materials informatics for materials discovery and design, to both researchers and educators," Rajan said. "It has been a good example of using cyberinfrastructure in materials science"

The presentation about the collaboration was part of a symposium about "Teaching and Learning in the Digital Age: Reliable Resources Across the Disciplines."

Laura Bartolo, professor and director of Kent State University's Center for Materials Informatics, spoke about the materials science collaboration.