Alexey I. Berdyugin^8,9,1,†

• ¹School of Physics and Astronomy, University of Manchester, Manchester M13 9PL, United Kingdom
• ²National Graphene Institute, University of Manchester, Manchester M13 9PL, United Kingdom
• ³Department of Physics, Washington University in St. Louis, St. Louis, Missouri 63130, USA
• ⁴Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
• ⁵Department of Physics, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp, Belgium
• ⁶Henry Royce Institute for Advanced Materials, The University of Manchester, Oxford Road, Manchester, M13 9PL, United Kingdom
• ⁷National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan
• ⁸Department of Materials Science and Engineering, National University of Singapore, 9 Engineering Drive 1, Singapore 117575, Singapore
• ⁹Department of Physics, National University of Singapore, 2 Science Drive 3, Singapore 117551, Singapore

• ^*Present address: Max Planck Institute for Solid State Research, D-70569 Stuttgart, Germany.
• ^†Contact author: alexey@nus.edu
• ^‡Contact author: shaffique@wustl.edu
• ^§Contact author: geim@manchester.ac.uk