1. Department of Physics & Astronomy, Hunter College, The City University of New York, 695 Park Avenue, New York, New York 10065, United States
2. The Graduate Center, The City University of New York, 365 Fifth Avenue, New York, New York 10016, United States
3. Materials Science and Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
4. Materials Research Institute, The Pennsylvania State University, University Park, Pennsylvania 16802, United States