1. Department of Physics, The University of Texas at El Paso, El Paso, Texas 79968, United States
2. Quantum Measurement Division, Physical Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, United States
3. Nanoscale Device Characterization Division, Physical Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, United States
4. Department of Physics, University of Alabama at Birmingham, Birmingham, Alabama 35233, United States
5. Materials Science Division, Argonne National Laboratory, Lemont, Illinois 60439, United States
6. Department of Chemical Engineering, Hampton University, Hampton, Virginia 23668, United States
7. Materials and Manufacturing Directorate, Air Force Research Laboratory, Wright-Patterson Air Force Base, Ohio 45433, United States
8. Department of Materials Science and Engineering, The Ohio State University, Columbus, Ohio 43210, United States
9. National Research Council, Washington, D.C. 20001, United States
10. Department of Engineering Technology, Middle Tennessee State University, Murfreesboro, Tennessee 37132, United States
11. Department of Astronomy and Physics, Vanderbilt University, Nashville, Tennessee 37235, United States
12. Department of Life and Physical Sciences, Fisk University, Nashville, Tennessee 37208, United States
13. Department of Materials Science and Engineering, Northwestern University, Evanston, Illinois 60208, United States