JAPAN - EDI

EXTREME ENERGY-DENSITY RESEARCH INSTITUTE
NAGAOKA UNIVERSITY OF TECHNOLOGY

Nagaoka, Niigata, 940-2188

Telephone: +81 258 47 9891
Telefax: +81 258 47 9890, or 9500
E-mail: yatsui@nagaokaut.ac.jp

Director:

Yatsui, Kiyoshi

Extreme Energy-Density Research Institute

Jiang, Weihua
Kinemuchi, Yoshiaki

Suematsu, Hisayuki
Suzuki, Tsuneo

Yang, Sung-Chae
Yatsui, Kiyoshi

Department of Electrical Engineering

Harada, Nobuhiro

Imada, Go

Irisawa, Juichi

Department of Chemical Engineering

Itoh, Haruhiko

Saitoh, Hidetoshi

Department of Mechanical Engineering

Masuda, Wataru

Suzuki, Masataro

Research activities:
Since the establishment in 1978 of our university by the government, we began R&D of pulse-power technology and its applications, which is mainly concerned with fusion research, materials science and lasers. In fusion, our main interests are (1) tight focusing of ion beams, (2) development of new ion diodes, (3) ion beam-target interaction, (4) development of new diagnostic techniques, (5) development of an induction voltage adder or an induction linac, (6) development of a quick-charging pulse-forming line, and so on.

Using a self-magnetically insulated plasma focus ion diode, we have achieved very tight focusing of ion beams (diameter 0.36mm). A power density of 1TW/cm² has been obtained. Using a 2-D PIC simulation code, we have reached a clear understanding of the process and reasonable agreement is obtained between experiment and simulation. Proton beam-target interaction has been studied, resulting in an estimated plasma temperature of 30eV. Using the reaction with the ion-beam ablation plasma, we have achieved the foil acceleration up to 8km/s and 13 GPa of ablation pressure. In addition, using the pulse-power technology, we have studied and developed highly repetitive pulsed power generators. The associated studies on the applications have been carried out. Furthermore, using the ablated plasma produced by ion beam interaction with targets, we have demonstrated the possibility of quick preparation of various thin films by ion beam evaporation techniques. The basic characteristics of the ablation plasma have been clarified both experimentally and theoretically. By rapid cooling of the ablation plasma, we have succeeded in an efficient production of ultra fine powders whose particles have a diameter typically less than 30nm.

The total number of people working in our group is approximately 60, which includes staff and undergraduate/graduate students.