1. National Institute for Materials Science, High pressure group, Namiki 1-1, Tskuba, Ibaraki 305-0044, Japan
2. Department of Materials Science, Osaka Prefecture University, 1-1 Gakuencho,
Naka-ku, Sakai, Osaka 599-8531, Japan
3. National Institute for Materials Science, Next generation semiconductor group, Namiki 1-1, Tskuba, Ibaraki 305-0044, Japan
4. Department of Applied Chemistry, Chubu University, 1200 Matsumoto, Kasugai, Aichi 487-8501, Japan
5. National Institute for Materials Science, International Center for Materials Nanoarchitectonics, Namiki 1-1, Tskuba, Ibaraki 305-0044, Japan