1. Advanced Technology Research Laboratories, Panasonic Corporation, 3-4 Hikaridai, Seika, Kyoto 619-0237, Japan
2. Panasonic Excel Staff Co., Ltd., 612 Suiginya, Shimogyo, Kyoto 600-8411, Japan
3. Graduate School of Material Science, Nara Institute of Science and Technology, 8916-5 Takayama, Ikoma, Nara 630-0192, Japan
4. CREST, JST, CREST, Japan Science and Technology Agency, 4-1-8 Honcho, Kawaguchi, Saitama 332-0012, Japan