1. Department of Materials, Imperial College London, South Kensington, London SW7 2AZ, United Kingdom
2. U.K. SuperSTEM, Daresbury Laboratory, Daresbury, Cheshire WA4 4AD, United Kingdom
3. The Nanoscience Centre, University of Cambridge, 11 J.J. Thompson Avenue, Cambridge CB3 OFF, United Kingdom
4. Multiimaging Centre, Department of PDN (Physiology, Development and Neuroscience), Anatomy Building, University of Cambridge, Downing Street, Cambridge CB2 3DY, United Kingdom
5. Department of Materials Science and Metallurgy, University of Cambridge, Pembroke Street, Cambridge CB2 3QZ, United Kingdom