1. Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
2. Department of Applied Physics, Stanford University, Stanford, California 94305, United States
3. Department of Physics, Stanford University, Stanford, California 94305, United States
4. Corporate Research, Taiwan Semiconductor Manufacturing Company (TSMC), Hsinchu 300, Taiwan
5. Department of Mechanical Engineering, University of Hong Kong, Pok Fu Lam, Hong Kong