1. Department of Materials Science and Engineering, Johns Hopkins University, Baltimore, Maryland 21218, United States
2. Department of Physics and Astronomy, George Mason University, Fairfax, Virginia 22030, United States
3. Applied Mathematics and Computational Research Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
4. Sandia National Laboratories, Livermore, California 94550, United States
5. Department of Nuclear Engineering, University of Tennessee, Knoxville, Tennessee 37916, United States
6. Center for Integrated Nanotechnologies, Sandia National Laboratories, Albuquerque, New Mexico 87123, United States
7. Department of Materials Science and Engineering, Lehigh University, Bethlehem, Pennsylvania 18015, United States