102 citations · 466 across the 48 of their papers we have counts for
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Electronic-Entropy-Driven Phase Transitions in Compressed Iron Oxides
S. Azadi, S. M. Vinko, C. Crepisson +3
Electronic entropy is usually treated as a secondary correction to structural stability, but under strong electronic excitation it can become a primary thermodynamic driving force.…
From Entropy to Compression: Competing Thermodynamic Drivers of Structural Transitions in Transition Metals
S. Azadi, S. M. Vinko, A. Principi +2
Solid-solid phase transitions in metals are traditionally driven by changes in density or external pressure. Here we show that, under strong electronic excitation, structural stabi…
Volume Collapse Without a Structural Transition in Shock-Compressed FeO
C. Crépisson, T. Stevens, M. Fitzgerald +121
We report x-ray diffraction and emission spectroscopy of FeO under laser-driven shock compression between 31-199 GPa. FeO retains the B1 (rocksalt) structure along the Hugoniot to…
Electronic-Entropy-Driven Solid-Solid Phase Transitions in Elemental Metals
S. Azadi, S. M. Vinko, A. Principi +2
We compute the thermodynamic phase diagram of seventeen elemental metals with hexagonal close-packed (hcp), face-centered cubic (fcc), and body-centered cubic (bcc) crystal structu…
Structural evolution of iron oxides melts at Earth's outer-core pressures
Céline Crépisson, Mila Fitzgerald, Domenic Peake +32
Oxygen and other light elements comprise up to 5 wt% of the Earth's outer-core, and may significantly influence its physical properties and the operation of the geodynamo. Here we…
Electronic Temperature-Driven Phase Stability and Structural Evolution of Iron at High Pressure
S. Azadi, S. M. Vinko
We present Gibbs free-energy phase diagrams for compressed iron within a pressure range of 20 to 300 GPa and electronic temperature up to 3 eV obtained using finite-temperature den…
Shock-driven amorphization and melt in FeO
Céline Crépisson, Alexis Amouretti, Marion Harmand +28
We present measurements on FeO amorphization and melt under laser-driven shock compression up to 209(10) GPa via time-resolved in situ x-ray diffraction. At 122(3) GPa, a d…
Phase transitions of FeO under laser shock compression
A. Amouretti, C. Crépisson, S. Azadi +22
We present in-situ x-ray diffraction and velocity measurements of FeO under laser shock compression at pressures between 38-116 GPa. None of the phases reported by static c…
Resonant inelastic x-ray scattering in warm-dense Fe compounds beyond the SASE FEL resolution limit
Alessandro Forte, Thomas Gawne, Karim K. Alaa El-Din +19
Resonant inelastic x-ray scattering (RIXS) is a widely used spectroscopic technique, providing access to the electronic structure and dynamics of atoms, molecules, and solids. Howe…
A Rate Model of Electron Populations for Non-linear High-Fluence X-ray Absorption Near-Edge Spectra
Robin Y. Engel, Markus Scholz, Jan O. Schunck +1
Absorbing a focused, femtosecond X-ray pulse from a Free-Electron Laser (FEL) can lead to extreme electronic excitations in solids. This excitation drives changes of the electronic…
Electron Dynamics at High-Energy Densities in Nickel from Non-linear Resonant X-ray Absorption Spectra
Robin Y. Engel, Oliver Alexander, Kaan Atak +40
The pulse intensity from X-ray free-electron lasers (FELs) can create extreme excitation densities in solids, entering the regime of non-linear X-ray-matter interactions. We show L…