1. School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, UK, Self-Organizing Molecular Systems (SOMS) Centre, University of Leeds, Leeds LS2 9JT, UK, I/O group/Technology Platform Research CentreSeiko Epson Corporation, Fujimi Plant: 281 Fujimi, Fujimi-machi, Suwa-gun, Nagano-ken 399-0293, Japan, and Cambridge Research Laboratory of Epson, 9A Science Park, Milton Rd, Cambridge CB4 0FE, UK