I am a senior scientist at ISIS, conducting a research program in condensed matter physics, and with responsibility for developing techniques and software to study dynamics in single crystals.
Research and development interests
My scientific research revolves around strongly correlated electron materials. These are systems where the behaviour of the electrons cannot be understood as arising from their motion an average field due to all the other electrons, but instead depend on the subtle interplay of the spin, charge, orbital and lattice degrees of freedom in the materials. In consequence, they can display unexpected ground states and have physical properties that are extremely sensitive to externally applied stimuli such as a magnetic field. I have a long-running programme studying colossal magnetoresistive manganites, and I am also part of long-standing collaborations studying the spin excitations in high-transition temperature superconductors. My other interests include quantum fluctuations in one and two dimensional model magnets, frustrated magnetism, spin dynamics in elemental ferromagnets and the classic weak itinerant ferromagnet MnSi. Most recently, I have been studying the magnetism of the recently discovered iron pnictide superconductors.
Neutron Instrument and experimental techniques
The majority of my scientific work has been carried out at ISIS, where I performed experiments that were instrumental in establishing single crystal spectroscopy on time-of-flight instruments as a routine probe of magnetic dynamics. I was project scientist responsible for the scientific and technical specification and commissioning of the MAPS spectrometer, and author of the Tobyfit program to account for instrument resolution in model fitting to data from chopper spectrometers. Most recently, I have been developing methods and software to fully map the complete four-dimensional wave-vector and energy dependence of magnetic and structural dynamics in single crystals, and using the approach in conjunction with ab initio calculations to understand the magnetic and lattice dynamics in the systems studied.
Excitations software home page: click here
Web pages for software projects:
Data correction and reduction for chopper spectrometers: Libisis
Visualising and analysing multi-dimensional neutron data: Horace
Fitting of resolution broadened models to data: Tobyfit
Grants, awards, teaching and other activities
Honorary Professor of Physics, University College London
For a list of publications this person has been involved with please see