Superconductivity is a phenomenon that occurs when a material has no electron res- istance under specific temperatures. The first recorded observation of the phenomenon was 100 years ago, and the Fe-based super- conductor was discovered in 2009. The key to open the secret of the Fe-based superconductor was found by a Korean-German corporative research team, supported by Ministry of Science ICP and Future Planning, National Research Foundation of Korea, Max-Planck Institute of Korea-POSTECH, and Institute for Basic Science.
The team, consisting of Doctor Baek Seung-ho (IFW-Dresden, Leibniz Institute for Solid State and Materials Research Dresden in German), Professor Kim Jun-sung (PHYS), and Ok Jong-mok (PHYS M.S.-Ph.D. integrated), announced the unique superconductivity phenomena of FeSe, an Fe-based superconductor, in Nature Materials. They discovered that nematic state temperature, on which molecules spread irregularly but toward the same direction in LCD magnified 300 times, is much higher than superconductivity temperature because of the degree of freedom of the Fe-based superconductor orbital related to electron distribution. This research sheds light on the cause of nematic state and how it affects superconductivity.