Probing extreme states of matter using high resolution inelastic X-ray free electron lasers

Abstract
I will discuss the investigation of ultrafast phenomena occurring in matter generated by high-intensity femtosecond optical pulses. Studies have shown that for gold the interatomic potential can be perturbed at sufficiently high laser intensities leading to an increase of its phonon energies, a phenomenon known as phonon hardening. Despite efforts to show the existence this behavior, the interpretation of the experimental data remains ambiguous. Here, I will present our recent results on phonon hardening using in situ single-shot x-ray diffraction at an XFEL. Building upon these results, I will introduce high-resolution inelastic X-ray scattering as a diagnostic to provide a model-free measurement of phonon hardening.

Bio
Adrien Descamps received his PhD in 2023 from the High Energy Density Science division at SLAC National Laboratory under the supervision of Prof. Glenzer. He is currently a postdoctoral fellow at Queen’s University Belfast under the supervision of Dr. McBride. He was recently awarded the Leverhulme Early Career Award to pursue his work on developing high-resolution inelastic X-ray scattering for extreme states of matter.