The pace of modern technological development - from microelectronics to catalysts, to coatings - is driven by fundamental breakthroughs in fabricating novel nano-structured materials. Such materials often promise unique or enhanced physical characteristics, such as strong magnetisation or unusual reactivity. These characteristics will derive from, but can also be compromised by, subtle, atomic-scale structural variations. In each case, nano-resolved characterization is essential and full understanding of a material demands multiple state-of-the-art experimental probes. The probes used in my research include beams of electrons, atoms, ions, and photons, as well as physical devices such as the tip of an atomic force microscope. Each probe has its advantages and its limitations and the best studies of nanostructured material combine the results from several probes in order to develop a complete description.

A selection of my recent projects is given below. The uppermost projects derive from my time in Glasgow, whilst some of those below are based on collaboration with colleagues in Cambridge, where more information can be found.

• Pulsed Laser Deposition
• Nanoparticle characterization
• Structural characterization of nanomaterials
• Analytical electron microscopy
• X-ray spectroscopy
• Atom interferometry
• Development of Scanning Helium Microscopy
• Studies of thin film growth
• Medium energy ion scattering
• Gas detection via field ionisation from carbon nanotubes

X-ray spectroscopy

The intense, microfocused x-ray probe now available at the Diamond Light Source provides another route to spatially-resolved chemical analysis, offering higher energy resolution but lower spatial resolution than the analytical electron microscopy studies outlined above. These synchrotron-based studies also allow the energy of the probe to be varied, offering a wider range of experimental techniques, and the polarisation to be tuned. Tunable polarisation is of particular interest in the study of magnetic materials and of chiral samples. We recently undertook a study of such chiral samples, looking at the electrons ejected from a gold sample that can be etched to form two similar, but mirror-image structures. Intriguingly, the electron current ejected by the x-ray beam depends strongly on the polarisation of the x-rays, which hints at a new type of chiral filtering effect. Publications: 26.