1. Center for Electron Microscopy, Steyrergasse 17, 8010 Graz, Austria
2. Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
3. EMPA, Swiss Federal Laboratories for Materials Science and Technology, Laboratory for Mechanics of Materials and Nanostructures, Feuerwerkerstrasse 39, 3602 Thun, Switzerland
4. Department of Materials Science and Engineering, University of Tennessee, Knoxville, Tennessee 37996, United States
5. Institute for Electron Microscopy and Nanoanalysis, Graz University of Technology, 8010 Graz, Austria