My main research activities are currrently linked with X-ray Free Electron Laser experiments and data analysis. Particularly interested in planetary science I am currently working on XRD data of dynamically compressed material to better understand the Earth and Super-Earth interiors. With a geophysical background, my PhD and previous research experiences in France, Edinburgh and Australia were focused on static compression (Diamond Anvil Cell and Paris Edinburgh Press) experiments at synchrotron sources and simple DFT calculation to understand behaviour of elements, minerals and melts under high pressure.
Research interests
planetary science
XFEL
XRD
static and dynamic compression
Selected publications
Phase transitions of Fe2O3 under laser shock compression
under review for Physical Review Letters
Abstract:
We present in-situ x-ray diffraction and velocity measurements of Fe2O3 under laser shock compression at pressures between 38-116 GPa. None of the phases reported by static compression studies were observed. Instead, we observed an isostructural phase transition from α-Fe2O3 to a new α′-Fe2O3 phase at a pressure of 50-62 GPa. The α′-Fe2O3 phase differs from α-Fe2O3 by an 11% volume drop and a different unit cell compressibility. We further observed a two-wave structure in the velocity profile, which can be related to an intermediate regime where both α and α′ phases coexist. Density functional theory calculations with a Hubbard parameter indicate that the observed unit cell volume drop can be associated with a spin transition following a magnetic collapse.