Author Affiliations

S. Chakraborty,^1,* O. P. Marshall,¹ Y.-J. Kim,^2,3 K. S. Novoselov,² H. E. Beere,⁴ and D. A. Ritchie⁴

¹Microelectronics and Nanostructures, School of Electrical and Electronic Engineering, University of Manchester, Manchester, M13 9PL, UK

²School of Physics and Astronomy, University of Manchester, Manchester M13 9PL, UK

³Department of Chemistry, College of Natural Sciences, Seoul National University, Seoul, 151-747, Korea

⁴Semiconductor Physics Group, Cavendish Laboratory, University of Cambridge, JJ Thomson Avenue, Cambridge, CB3 0HE, UK

^*Corresponding author: s.chakraborty@manchester.ac.uk