Activities in Katori Group



Every Monday during 3rd period, we take Magnetism in Condensed Matter (Oxford Master Series) in rotation to study the basics of magnetism.


Progress report meeting

Every Thursday during 4th period, students and staff report on their research progress and discuss and consult on future research policies.


Journal Club

Every Thursday during 2nd period, we introduce papers with the aim of exchanging information on recent research trends and technology introductions, as well as exploring new research themes from a broad perspective.



Round 1(4/21):Kazuhiro Wakasugi(M1)

Observation of superconductivity at 30~46K in AxFe2Se2 (A=Li, Na, Ba, Sr, Ca, Yb, and Eu)
T. P. Ying, et al., Sci. Rep., 2 426(2012)
The phase responsible for superconductivity in FeSe with metal insertions has been discussed because the electronic structure of the superconductor is different from that found in FeAs. The synthesis of new isomorphous chalcogenides containing alkali and alkaline-earth metals to elucidate this superconducting phase has been unsuccessful. We have succeeded in synthesizing a superconductor with a relatively high superconducting transition temperature of 30~46 K by intercalating alkali, alkaline-earth, and rare-earth metals between FeSe layers at low temperatures using an ammonothermal method using liquid ammonia. As a result, it was found that metal intercalation is possible at low temperatures due to the function of ammonia and that electron doping induces superconductivity. This result may provide a new starting point for understanding superconductivity and its mechanism in doped FeSe systems.