1. Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
2. Center for Integrated Nanotechnologies, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
3. State Key Laboratory for Mechanical Behavior of Materials, Xi’an Jiaotong University, Xi’an 710049, China
4. Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
5. Department of Materials Design and Innovation, University at Buffalo—The State University of New York, Buffalo, New York 14260, USA
6. Division of Quantum Phases & Devices, Department of Physics, Konkuk University, Seoul 143-701, South Korea