Recent discovery of the high-Tc superconductivity in Pu compounds reveals that it is important to clarify the electronic states experimentally in the transuranium compounds. Nevertheless, there are no experimental reports because of the high radioactivity. We succeeded in growing high quality single crystals of NpGe3 and NpRhGa5 and observed the de Haas-van Alphen effect. The Fermi surfaces were determined by the experiments and theoretical calculations consistently. The 5f electron of Np plays a role of both conductivity and magnetism, forming heavy electronic states. The result was published in J. Phys.: Condens. Matter and the article has been selected for "IOP Select". The result was also reported on the top page of Kahoku-Shimpo on May 18. The work has been done in collaboration with Osaka University, Kyoto-Sangyo University and Japan Atomic Research Institute.
図 Cryogen-free 27.5T hybrid magnet