David’s research is dedicated to the development and application of novel, accurate, but computationally tractable methodology for atomistic electronic structure simulations, both of solid state materials and molecular systems. David’s group focuses on the interface between techniques for treating large length-scales, the strong electronic correlations almost ubiquitous in systems of technological interest, and theoretical spectroscopy. He is actively involved in the development of linear-scaling density functional theory. Here, his group implements and improves corrective approaches such as DFT+U, constrained DFT and DFT+DMFT, as well as researching new Wannierisation and time propagation (TDDFT) algorithms. He maintains a long-term programme in the development of tractable and easily-used methods moving beyond Kohn-Sham DFT, via the density-matrix and Green's function, not only for spectra but for energies and their derivatives. He is interested in multiferroic and multiple-valence properties, generally, he has worked on predicting optical, magneto-optical, and photoemission spectroscopies. A particular focus is placed on these properties as exhibited by transition-metal comprising materials, complexes, and nanostructures. At present, applications of these materials to new high-density energy and data-storage technologies are receiving considerable attention. David and his team collaborate extensively with leading scientists from diverse fields including nanostructure fabrication, high-performance computing, and condensed matter theory.
David graduated with a BSc Joint Hons. (First Class) in Mathematics and Physics from University College Cork in 2007, whereupon he undertook study at the University of Cambridge with a National University of Ireland Travelling Studentship. He completed his PhD at the Cavendish Laboratory and Pembroke College, University of Cambridge in 2011, his thesis was published in the invited Springer Theses series, and intellectual property resulting from his research was commercialised. He undertook post-doctoral research at the University of Cambridge and the École Polytechnique Fédérale de Lausanne, Switzerland. In 2014, he was appointed to the academic staff of the School of Physics, as Assistant Professor, and now leads a growing research group with collaborative activity ranging from abstract electronic-structure theory, through high-performance software development, up to applied simulation facing industry.
Corrective approaches to DFT for strong interactions and self-interaction errors
Advanced and new applications of constrained density-functional theory
Linear-scaling electronic structure methods, and in situ optimisation of orbitals
Theoretical spectroscopy, particularly chiroptical and effects beyond linear-response
Non-adiabatic interactions, particularly in the vein of the dynamical Hubbard U.
See Publications page for updated list.