ＭＲＳ-J News Vol.14 No.3  Aug. 2002

To the Overseas Members of MRS-J

■Materials and Radiation Measurements…p.1
Professor Masaharu NAKAZAWA, Dept. of Quantum Enginering and Systems Science, School of Enginering, University of Tokyo
　The research study area of author is the radiation measurement, and in the connection of material research the author have discussed several topics of radiation sensors, such as superconducting X-ray spectrometer, micro-strip gas counter (MSGC), and room temperature semiconductors.
　The important change of customers of radiation detectors can be said from the nuclear industry to medical areas, it causes several influences on scientific research study works, especially its frame works.

■Correlated Electron Research Center, National Institute of Advanced Industrial Science and Technology…p.3
Dr. Hiroshi AKOH, AIST
　Correlated Electron Research Center (CERC) aimes at exploring new quantum-functional materials and developing new quantum-devices on the basis of emerging physical science on correlated electron system. The term “correlated electrons” represents the state of matter where many electrons are strongly interacting with each other, forming the liquid-, solid-, and liquid-crystal-like state of electrons. Those electronic phases can be switched by external stimuli, which causes drastic changes in magnetic, electrical and optical properties. Such a phase switching can be as fast as one picosecond or less. The correlated electron technology will utilize this gigantic phase-response of electrons as the out-put functionality.

■MgB₂ Thin Films and Josephson Junctions…p.5
Dr. Zhen WANG, Leader, Superconductive Electronics Group, Kansai Advanced Research Center, Communications Research Laboratory
　The recent discovery of superconductivity with critical temperature Tc〜39K in magnesium diboride (MgB2) not only caused excitement in the solid states physics community but also generated interest in using MgB2 instead of conventional superconducting materials for superconducting electronics. We have recently made some advances in the development of as-grown MgB2 thin films and Josephson tunnel junctions based on the as-grown MgB2 films. The MgB2 thin films we made were fabricated by using a conventional multiple-target sputtering system at a low substrate temperature without performing a post-annealing process, and MgB2/AlN/NbN Josephson tunnel junctions fabricated by using much the same trilayer technique used to fabricate Nb tunnel junctions showed excellent Josephson tunneling and quasi-particle tunneling properties.