1. Japan Fine Ceramics Center, Joint Research Consortium of Frontier Carbon Technology, c/o Research Center for Advanced Carbon Materials, AIST Tsukuba Central 5, 1-1-1 Higashi, Tsukuba, 305-8565, Japan
2. Research Center for Advanced Carbon Materials, AIST Tsukuba Central 5, 1-1-1 Higashi, Tsukuba, 305-8565, Japan