1. Department of Materials Science and Engineering, University of California, Los Angeles, 410 Westwood Plaza, Los Angeles, California 90095, United States
2. Irvine Materials Research Institute (IMRI), University of California, Irvine, 644 Engineering Tower, Irvine, California 92697, United States
3. Graduate Department of Micro-Nano Mechanical Science and Engineering, Nagoya University, Furo-cho, Nagoya 464-8601, Japan
4. Department of Mechanical Engineering and Materials Science Program, Colorado School of Mines, Golden, Colorado 80401, United States
5. Department of Materials Science and Engineering, Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24061, United States