1. Department of Physics, Center for Advanced Nanoscience, University of California, San Diego, California 92093, USA
2. Department of Quantum Matter Physics, University of Geneva, 24 Quai Ernest-Ansermet, CH-1211 Geneva, Switzerland
3. Faculty of Materials Science and Engineering, Technion-Israel Institute of Technology, 32000 Haifa, Israel
4. Departamento de Física de Materiales, Universidad Complutense de Madrid, 28040 Madrid, Spain
5. Laboratoire de Physique des Solides, CNRS, Université Paris Saclay, 91405 Orsay Cedex, France