Publications associées à EXAFS structural determination of the Pt2(P2O5H2)44- anion in solution

A compact approach to higher-resolution resonant inelastic x-ray scattering detection using photoelectrons

The detection of inelastically scattered soft x-rays with high energy resolution usually requires large grating spectrometers. Recently, photoelectron spectrometry for analysis of x-rays (PAX) has been rediscovered for modern spectroscopy experiments at sy ...

Iop Publishing Ltd2024

Impact of microwave beam scattering by density fluctuations on the electron-cyclotron power deposition profile in tokamaks

Stefano Coda, Joan Decker, Jean Arthur Cazabonne, Umesh Kumar, Oleg Krutkin

Electron-cyclotron waves are a tool commonly used in tokamaks, in particular to drive current. Their ability to drive current in a very localized manner renders them an optimal tool for MHD mode mitigation. However, such applications require high accuracy ...

IOP Publishing Ltd2024

Electronic structure and lattice dynamics of 1T-VSe2:Origin of the three-dimensional charge density wave

Ji Dai, Lorenzo Monacelli

To characterize in detail the charge density wave (CDW) transition of 1T-VSe2, its electronic structure and lattice dynamics are comprehensively studied by means of x-ray diffraction, muon spectroscopy, angle resolved photoemission (ARPES), diffuse and ine ...

Amer Physical Soc2024

Spin wave dispersion of ultra-low damping hematite (α-Fe2O3) at GHz frequencies

Dirk Grundler, Ferdinand Rémy Hynek Posva, Mohammad Hamdi

Raw data associated to the manuscript ‘’Spin wave dispersion of ultra-low damping hematite (α-Fe2O3) at GHz frequencies‘’, Physical Review Materials 7, 054407(2023); doi: 10.1103/PhysRevMaterials.7.054407 Information about file fo ...

Zenodo2023

Spin wave dispersion of ultra-low damping hematite ( α−Fe2O3 ) at GHz frequencies

Dirk Grundler, Ferdinand Rémy Hynek Posva, Mohammad Hamdi

Low magnetic damping and high group velocity of spin waves (SWs) or magnons are two crucial parameters for functional magnonic devices. Magnonics research on signal processing and wave-based computation at GHz frequencies focused on the artificial ferrimag ...

2023

Broadband spectroscopy and inelastic light scattering on the canted antiferromagnet hematite for antiferromagnetic magnonics

Mohammad Hamdi

Collective spin excitations propagating in magnetically ordered materials are called spin waves (SWs) or magnons. They are promising for low-power and beyond-CMOS information processing, which do not suffer from the ohmic losses. SWs in ferromagnets (antif ...

EPFL2023

Nonlinear Inverse Problems in Quantitative Phase Imaging

Thanh-An Michel Pham

The topic of this thesis is the development of new algorithmic reconstruction methods for quantitative phase imaging (QPI). In the past decade, advanced QPI has emerged as a valuable tool to study label-free biological samples and uncover their 3D structur ...

EPFL2022

Evidence for a spin acoustic surface plasmon from inelastic atom scattering

Davide Campi

Closed-shell atoms scattered from a metal surface exchange energy and momentum with surface phonons mostly via the interposed surface valence electrons, i.e., via the creation of virtual electron-hole pairs. The latter can then decay into surface phonons v ...

Nature Research2021

Photo- and thermally-induced electronic and structural dynamics in perovskites and transition metal oxides

Oliviero Cannelli

In this thesis, we exploited optical and X-ray pump-probe methods in a synergistic approach to study the interplay of the electronic, spin and structural degrees of freedom in two class of complex systems relevant for solar energy conversion applications: ...

EPFL2021

Differential steric effects in the inelastic scattering of NO(X) plus Ar: spin-orbit changing transitions

Sean Dennis Steven Gordon

Spin-orbit changing transitions for bond-axis oriented collisions of NO(X) with Ar have been investigated with full quantum state selection via a crossed molecular beam experiment at collision energies of 532 cm(-1) and 651 cm(-1). NO(X) molecules were sel ...

2019

Soft-phonon driven hexagonal-orthorhombic phase transition in BaVS3

Helmuth Berger

The lattice dynamics of low-dimensional BaVS3 is reported across the hexagonal-orthorhombic phase transition occurring at T-S = 250 K using a combination of the thermal diffuse scattering of x rays, inelastic x-ray scattering, and density functional theory ...

2019

Tokamak plasma edge studies by microwave short-pulse reflectometry and backscattering

Pedro Andres Molina Cabrera

Moving towards an increased understanding of the dynamic processes in the edge of tokamak plasmas requires continuous innovation in diagnostic capabilities, pushing the envelope in both spatial and temporal dimenstions. Plasma density and rotation, and the ...

EPFL2019

Spin polarization and attosecond time delay in photoemission from solids

Mauro Fanciulli

In the photoemission process electrons are emitted from a solid upon excitation with UV light. From the measurement of their energy and momentum, angle-resolved photoemission spectroscopy (ARPES) allows to reconstruct the electronic properties of the solid ...

EPFL2018

Efficient Inversion of Multiple-Scattering Model for Optical Diffraction Tomography

Michaël Unser, Thanh-An Michel Pham, Emmanuel Emilien Louis Soubies

Optical diffraction tomography relies on solving an inverse scattering problem governed by the wave equation. Classical reconstruction algorithms are based on linear approximations of the forward model (Born or Rytov), which limits their applicability to t ...

2017

Control of pulsed light propagation through multimode optical fibers

Edgar Emilio Morales Delgado

Visualization of organs and cells in the interior of living beings is a challenging task due to the light absorption and multiple light scattering occurring in biological tissue that prevents the di-rect transmission of images. A standard visualization app ...

EPFL2017

X‑ray and Neutron Scattering of Water

Livia Eleonora Bove Kado

This review article focuses on the most recent advances in X-ray and neutron scattering studies of water structure, from ambient temperature to the deeply supercooled and amorphous states, and of water diffusive and collective dynamics, in disparate thermo ...

American Chemical Society2016

Surface origin and control of resonance Raman scattering and surface band gap in indium nitride

Esther Alarcon Llado

Resonance Raman scattering measurements were performed on indium nitride thin films under conditions where the surface electron concentration was controlled by an electrolyte gate. As the surface condition is tuned from electron depletion to accumulation, ...

Iop Publishing Ltd2016

Beyond structure: ultrafast X-ray absorption spectroscopy as a probe of non-adiabatic wavepacket dynamics

Majed Chergui, Simon Neville

The excited state non-adiabatic dynamics of polyatomic molecules, leading to the coupling of structural and electronic dynamics, is a fundamentally important yet challenging problem for both experiment and theory. Ongoing developments in ultrafast extreme ...

Royal Soc Chemistry2016

Energy-selective neutron imaging for materials science

Steven Luc X Peetermans

Common neutron imaging techniques study the attenuation of a neutron beam penetrating a sample of interest. The recorded radiograph shows a contrast depending on traversed material and its thickness. Tomography allows separating both and obtaining 3D spati ...

EPFL2015

Orbital occupancies and the putative j(eff)=1/2 ground state in Ba2IrO4: A combined oxygen K-edge XAS and RIXS study

Henrik Moodysson Rønnow

The nature of the electronic ground state of Ba2IrO4 has been addressed using soft x-ray absorption and inelastic scattering techniques in the vicinity of the oxygen K edge. From the polarization and angular dependence of x-ray absorption spectroscopy (XAS ...

Amer Physical Soc2014