A. I. Berdyugin
School of Physics and Astronomy, University of Manchester, Manchester M13 9PL, UK.
S. G. Xu
School of Physics and Astronomy, University of Manchester, Manchester M13 9PL, UK.National Graphene Institute, University of Manchester, Manchester M13 9PL, UK.
F. M. D. Pellegrino
Dipartimento di Fisica e Astronomia, Università di Catania, Via S. Sofia, 64, I-95123 Catania, Italy.INFN, Sez. Catania, I-95123 Catania, Italy.
R. Krishna Kumar
School of Physics and Astronomy, University of Manchester, Manchester M13 9PL, UK.National Graphene Institute, University of Manchester, Manchester M13 9PL, UK.
A. Principi
School of Physics and Astronomy, University of Manchester, Manchester M13 9PL, UK.
I. Torre
ICFO–Institut de Ciencies Fotoniques, The Barcelona Institute of Science and Technology, 08860 Castelldefels (Barcelona), Spain.
M. Ben Shalom
School of Physics and Astronomy, University of Manchester, Manchester M13 9PL, UK.National Graphene Institute, University of Manchester, Manchester M13 9PL, UK.
T. Taniguchi
National Institute for Materials Science, 1‐1 Namiki, Tsukuba, 305‐0044 Japan.
K. Watanabe
National Institute for Materials Science, 1‐1 Namiki, Tsukuba, 305‐0044 Japan.
I. V. Grigorieva
School of Physics and Astronomy, University of Manchester, Manchester M13 9PL, UK.
M. Polini
School of Physics and Astronomy, University of Manchester, Manchester M13 9PL, UK.Istituto Italiano di Tecnologia, Graphene Labs, Via Morego 30, 16163 Genova, Italy.
A. K. Geim
School of Physics and Astronomy, University of Manchester, Manchester M13 9PL, UK.National Graphene Institute, University of Manchester, Manchester M13 9PL, UK.
D. A. Bandurin
School of Physics and Astronomy, University of Manchester, Manchester M13 9PL, UK.
