1. Kawazoe Frontier Technologies Corporation, Kuden-cho 931-113, Sakae-ku, Yokohama 247-0014, Japan, Institute of Industrial Science, The University of Tokyo, Komaba 4-6-1, Meguro-ku, Tokyo 153-8505, Japan, and Materials and Structures Laboratory, Tokyo Institute of Technology, Nagatsuta 4259, Midori-ku, Yokohama 226-8503, Japan