1. James Franck Institute, University of Chicago, 929 E. 57th Street, Chicago, Illinois 60637, United States
2. Center for Nanoscale Materials, Argonne National Laboratory, 9700 S. Cass Avenue, Argonne, Illinois 60439 United States
3. Advanced Electron Microscopy Facility, University of Chicago, 929 E. 57th Street, Chicago, Illinois 60637 United States
4. Department of Physics, University of Chicago, 5720 S. Ellis Avenue, Chicago, Illinois 60637, United States