1. Collaboratory for Advanced Computing and Simulations, University of Southern California, Los Angeles, California 90089-0242, United States
2. Electrical Insulation Research Center, Institute of Materials Science, University of Connecticut, Storrs, Connecticut 06269, United States
3. School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
4. Department of Physics, Kumamoto University, Kumamoto 860-8555, Japan
5. Institute of Materials Science, University of Connecticut, Storrs, Connecticut 06269, United States