1. Department of Physics, Kumamoto University, Kumamoto 860-8555, Japan
2. Graduate School of System Informatics, Kobe University, Kobe 657-8501, Japan
3. Collaboratory for Advanced Computing and Simulations, Department of Physics & Astronomy, Department of Computer Science, Department of Chemical Engineering & Materials Science, Department of Biological Sciences, University of Southern California, Los Angeles, California 90089-0242, USA
4. Research Center for Condensed Matter Physics, Hiroshima Institute of Technology, Hiroshima 731-5193, Japan