Publications (25)
Unified understanding of the valence transition in the rare-earth monochalcogenides under pressure
Ignace Jarrige, Hitoshi Yamaoka, Jean-Pascal Rueff +10
Valence instability is a key ingredient of the unusual properties of f electron materials, yet a clear understanding is lacking as it involves a complex interplay between f electro…
Spectroscopies and electron microscopies unravel the origin of the first colour photographs
Victor de Seauve, Marie-Angélique Languille, Mathieu Kociak +7
The first colours photographs were created by a process introduced by Edmond Becquerel in 1848. The nature of these photochromatic images colours motivated a debate between scienti…
Depth-resolving the redox compensation mechanism in LixNiO2
Roberto Fantin, Thibaut Jousseaume, Raphael Ramos +4
The performances of lithium-ion batteries are set by the electrodes materials capacity to exchange lithium ions and electrons faster and reversibly. To this goal Ni-rich layered me…
Evidence for non-conventional pairing in NaCoOyHO
Jean-Pascal Rueff, M. Calandra, M. D'astuto +10
We report on first investigation of the lattice dynamics in the novel superconducting material NaCoO1.3HO and the non-hydrated parent compound Na$\_{0.7}…
A fundamental correlative spectroscopic study on LixNiO2 and NaNiO2
Quentin Jacquet, Nataliia Mozhzhukhina, Peter N. O. Gillespie +14
The intimate correlation between the local atomic arrangement and electronic states in Li-ion battery cathode materials plays a crucial role in determining their electrochemical pr…
Interface properties and built-in potential profile of a LaCrO/SrTiO superlattice determined by standing-wave excited photoemission spectroscopy
Shih-Chieh Lin, Cheng-Tai Kuo, Ryan B. Comes +14
LaCrO (LCO) / SrTiO (STO) heterojunctions are intriguing due to a polar discontinuity along (001), two distinct and controllable interface structures [(LaO)/(TiO)$^…
Unraveling p-type and n-type interfaces in Superconducting Infinite-Layer Nickelate thin films
Aravind Raji, Araceli Gutiérrez-Llorente, Dongxin Zhang +5
After decades of research, superconductivity was finally found in nickel-based analogs of superconducting cuprates, with infinite-layer (IL) structure. These results are so far res…
Temperature and pressure-induced spin-state transitions in LaCoO3
György Vankó, Jean-Pascal Rueff, Aleksi Mattila +2
We report the continuous variation of the spin moment of cobalt in LaCoO3 across its temperature and pressure-induced spin transitions evidenced with Kβemission spectra. The first…
Ultrafast Charge-Transfer and Auger Decay Processes in Aqueous CaCl Solution: Insights from Core-Level Spectroscopy
Denis Céolin, Tsveta Miteva, Jean-Pascal Rueff +6
Understanding the interaction between metal ions and their aqueous environment is fundamental in many areas of chemistry, biology, and environmental science. In this study, we inve…
Probing the gamma-alpha Transition in Bulk Ce under Pressure: A Direct Investigation by Resonant Inelastic X-ray Scattering
Jean-Pascal Rueff, Jean-Paul Itié, M. Taguchi +5
We report on the most complete investigation to date of the 4f-electron properties at the gamma-alpha transition in elemental Ce by resonant inelastic x-ray scattering (RIXS). The…
Inelastic X-ray Scattering by Electronic Excitations in Solids at High Pressure
Jean-Pascal Rueff, Abhay Shukla
Investigating electronic structure and excitations under extreme conditions gives access to a rich variety of phenomena. High pressure typically induces behavior such as magnetic c…
Charge distribution across capped and uncapped infinite-layer neodymium nickelate thin films
Aravind Raji, Guillaume Krieger, Nathalie Viart +3
Charge ordering (CO) phenomena have been widely debated in strongly-correlated electron systems mainly regarding their role in high-temperature superconductivity. Here, we elucidat…
Bulk electronic structure of non-centrosymmetric EuTGe3 (T= Co, Ni, Rh, Ir) studied by hard x-ray photoelectron spectroscopy
Yuki Utsumi, Deepa Kasinathan, Przemyslaw Swatek +4
Non-centrosymmetric EuTGe3 (T=Co, Ni, Rh, and Ir) possesses magnetic Eu2+ ions and antiferromagnetic ordering appears at low temperatures. Transition metal substitution leads to ch…
Electronic Structure of the Dilute Magnetic Semiconductor from Hard X-ray Photoelectron Spectroscopy and Hard X-ray Angle-Resolved Photoemission
Armela Keqi, Mathias Gehlmann, Giuseppina Conti +18
We have investigated the electronic structure of the dilute magnetic semiconductor (DMS) and compared it to that of an undoped reference sample, using h…
Tuning the dynamics of chiral domain walls of ferrimagnetic films with the magneto-ionic effect
Cristina Balan, Jose Pena Garcia, Aymen Fassatoui +6
The manipulation of magnetism with a gate voltage is expected to lead the way towards the realization of energy-efficient spintronics devices and high-performance magnetic memories…
Valence Instability of YbCuSi through its quantum critical point
A. Fernandez-Panella, V. Balédent, D. Braithwaite +4
We report Resonant inelastic x-ray scattering measurements (RIXS) in YbCuSi at the Yb L edge under high pressure (up to 22 GPa) and at low temperatures (down to 7 K)…
Dynamical screening in SrVO: Inelastic x-ray scattering experiments and ab initio calculations
Kari Ruotsalainen, Alessandro Nicolaou, Christoph J. Sahle +5
We characterize experimentally and theoretically the high-energy dielectric screening properties of the prototypical correlated metal SrVO. The dynamical structure factor measu…
Charge-transfer effect in hard x-ray 1 and 2 photoemission spectra: LDA+DMFT and cluster-model analysis
Mahnaz Ghiasi, Atsushi Hariki, Mathias Winder +6
We study and hard x-ray photoemission spectra (XPS) in a series of late transition metal oxides: FeO (3), FeTiO (3), CoO (3) and NiO (3$d…
Emergent electronic landscapes in a novel valence-ordered nickelate with tri-component nickel coordination
Aravind Raji, Zhengang Dong, Victor Porée +11
The metal-hydride-based topochemical reduction process has produced novel thermodynamically unstable phases across various transition metal oxide series with unusual crystal struct…
Pressure induced high-spin to low-spin transition in FeS evidenced by x-ray emission spectroscopy
Jean-Pascal Rueff, Chi-Chang Kao, Viktor V. Struzhkin +4
We report the observation of the pressure-induced high-spin to low-spin transition in FeS using new high-pressure synchrotron x-ray emission spectroscopy techniques. The transition…
Epsilon-iron as a spin-smectic state
Blair W. Lebert, Tommaso Gorni, Michele Casula +11
Using x-ray emission spectroscopy, we find appreciable local magnetic moments until 30-40 GPa in the high-pressure phase of iron, however no magnetic order is detected with neutron…
Two-dimensional electron systems in perovskite oxide heterostructures: Role of the polarity-induced substitutional defects
Shih-Chieh Lin, Cheng-Tai Kuo, Yu-Cheng Shao +17
The discovery of a two-dimensional electron system (2DES) at the interfaces of perovskite oxides such as LaAlO3 and SrTiO3 has motivated enormous efforts in engineering interfacial…
Orbital contributions in the element-resolved valence electronic structure of Bi2Se3
Cheng-Tai Kuo, Shih-Chieh Lin, Jean-Pascal Rueff +9
In this work, we studied the bulk band structure of a topological insulator (TI) Bi2Se3 and determined the contributions of the Bi and Se orbital states to the valence bands using…
Resonant inelastic x-ray scattering study of doping and temperature dependence of low-energy excitations in LaSrVO
Kari Ruotsalainen, Matteo Gatti, James M. Ablett +5
We present a temperature and doping dependent resonant inelastic X-ray scattering experiment at the V L and O K edges in LaSrVO for and . This…
Edmond Becquerel's colour photographic process involves a Ag/AgCl-based sensitized layer
Victor de Seauve, Marie-Angélique Languille, Stéphanie Belin +5
Edmond Becquerel invented in 1848 the first colour photographic process. The "photochromatic images" he produced raised several questions, among which the photochromic nature of th…