In their paper “Exploration of new superconductors and functional materials, and fabrication of superconducting tapes and wires of iron pnictides,” published in Science and Technology of Advanced Materials, researchers Hideo Hosono, Keiichi Tanabe, Eiji Takayama-Muromachi, Hiroshi Kageyama, Shoji Yamanaka, Hiroaki Kumakura, Minoru Nohara, Hidenori Hiramatsu and Satoru Fujitsu report on four years of extensive research on around 1,000 materials, with detailed insights learned from the new superconducting materials discovered and their potential for wires and devices. A unique feature of this review is its incorporation of roughly 700 studied materials that did not show superconductivity.
[pullquote]A unique feature of this review is its incorporation of roughly 700 studied materials that did not show superconductivity.[/pullquote]
“This is probably the first such paper with a list of experiments that failed,” says Hosono, a researcher at Tokyo Institute of Technology and first author of the review. “It should be invaluable data for researchers in the field.”
Existing theory offers little that helps identify high temperature conductors, leaving a vast array of material possibilities. “We decided not to waste the time and effort of other researchers and wrote this paper with the results of samples that did not go superconducting,” explains Hosono, who also led the research behind the first discovery of iron-based superconductors in 2006.
In the past, similar research projects have strictly focused on finding superconducting properties, resulting in an all-or-nothing outcome. At the time the work in the review was carried out, funding for superconductivity research was in decline. Hosono and his colleagues employed a flexible approach that led to valuable insights into other material properties, such as ammonia catalysis for fertilizer production, am bipolar oxide thin film transistors and metallic ferroelectricity.
The research team members were also unique for a project in superconductivity because their research expertise emphasized solid-state chemistry over condensed-matter physics. They included researchers from Tokyo Institute of Technology, the International Superconductivity Research Center, the National Institute of Materials Science, Kyoto University, Hiroshima University and Okayama University.
The paper is available online at IOPscience.