1. Institute of Physics University of Münster 48149 Münster Germany
2. Walter Schottky Institute Technical University of Munich 85748 Garching Germany
3. Physics Department Technical University of Munich 85748 Garching Germany
4. Department of Materials Science and Engineering The Pennsylvania State University University Park PA 16802 USA
5. Center for 2D and Layered Materials The Pennsylvania State University University Park PA 16802 USA
6. Department of Materials Science and Engineering National University of Singapore 9 Engineering Drive 1 Singapore 117575 Singapore
7. Centre for Advanced 2D Materials National University of Singapore 6 Science Drive 2 Singapore 117546 Singapore
8. Department of Materials Science and Engineering McMaster University 1280 Main St W Hamilton ON L8S 4L8 Canada
9. Materials Research Institute The Pennsylvania State University University Park PA 16802 USA
10. 2D Crystal Consortium The Pennsylvania State University University Park PA 16802 USA
11. Department of Physics National University of Singapore Singapore 117551 Singapore
12. Center for Atomically Thin Multifunctional Coatings The Pennsylvania State University University Park PA 16802 USA