Publications related to Backscatter

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

Kinetics of information scrambling in correlated metals: Disorder-driven transition from shock wave to Fisher or Kolmogorov-Petrovsky-Piskunov dynamics

Camille Didier Georges Aron

Quenched disorder slows down the scrambling of quantum information. Using a bottom-up approach, we formulate a kinetic theory of scrambling in a correlated metal near a superconducting transition, following the scrambling dynamics as the impurity scatterin ...

Amer Physical Soc2023

Study of backward Brillouin scattering in gas-filled anti-resonant fibers

Luc Thévenaz, Malak Mohamed Hossameldeen Omar Mohamed Galal, Li Zhang

Brillouin scattering in gas shows unmatched gain properties in hollow-core optical fibers filled at high pressure. Here, the gain characteristics are studied for two common gases, namely, N2 and CO2, which show distinct features and are compared to expecte ...

2023

Study on the possibility of Φ-OTDR sensing in hollow-core fibres

Luc Thévenaz, Malak Mohamed Hossameldeen Omar Mohamed Galal, Yuting Yang

The backscattering process in hollow core fibres shows a large similarity with Rayleigh scattering, offering the potential to be exploited for distributed sensing. A classical Φ-OTDR implementation is used to observe the backscattering signal from the surf ...

SPIE2023

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

Dirk Grundler, Mohammad Hamdi, Ferdinand Rémy Hynek Posva

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, Mohammad Hamdi, Ferdinand Rémy Hynek Posva

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

Confirming the high pressure phase diagram of the Shastry-Sutherland model

Henrik Moodysson Rønnow, Martin Mansson

A Muon Spin Rotation (mu+SR) study was conducted to investigate the magnetic properties of SrCu2(BO3)(2) (SCBO) as a function of temperature/pressure. Measurements in zero field and transverse field confirm the absence of long range magnetic order at high ...

IOP PUBLISHING LTD2023

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

Novel low-temperature fiber sensing technique using Brillouin scattering in gas

Luc Thévenaz, Yuting Yang, Marcelo Alfonso Soto Hernandez

Brillouin scattering in gases shows the unique property to offer an enhanced temperature sensitivity at very low temperatures. This attractive solution for cryogenic systems is justified theoretically and validated experimentally. ...

Optica Publishing Group2023

Historical perspective and basic principles

Luc Thévenaz

We give a broad overview of the historical development and physics of Brillouin scattering. We discuss the seminal papers of Brillouin and Mandelstam and give the historical context of their research. We discuss the development of experiments and observati ...

Elsevier2022

Spin waves in the collinear antiferromagnetic phase of Mn5Si3

Jan Persson

By combining two independent approaches, inelastic neutron-scattering measurements and density-functionaltheory calculations, we study the spin waves in the collinear antiferromagnetic phase (AFM2) of Mn5Si3. We obtain its magnetic ground-state properties ...

AMER PHYSICAL SOC2021

Raman tensor of zinc-phosphide (Zn3P2): from polarization measurements to simulation of Raman spectra

Anna Fontcuberta i Morral, Elias Zsolt Stutz, Santhanu Panikar Ramanandan, Mischa Samuel Flór, Jean-Baptiste Leran, Mahdi Zamani, Rajrupa Paul, Mirjana Dimitrievska

Zinc phosphide (Zn3P2) is a II–V compound semiconductor with promising photovoltaic and thermoelectric applications. Its complex structure is susceptible to facile defect formation, which plays a key role in further optimization of the material. Raman spec ...

2022

Static and dynamic properties of non-collinear quantum antiferromagnets explored by neutron scattering

Luc Testa

This thesis is devoted to the investigation of static and dynamic properties of two different sets of quantum magnets with neutron scattering techniques and the help of linear spin wave theory. Both systems are copper-based with spin-1/2, which makes them ...

EPFL2021

How Forward-Scattering Snow and Terrain Change the Alpine Radiation Balance With Application to Solar Panels

Michael Lehning, Annelen Kahl

Rough terrain in mid- and high latitudes is often covered with highly reflective snow, giving rise to a very complex transfer of incident sunlight. In order to simplify the radiative transfer in weather and climate models, snow is generally treated as an i ...

2021

Distributed optomechanical fiber sensing based on serrodyne analysis

Luc Thévenaz, Zhisheng Yang, Simon Adrien Zaslawski

Distributed measurement of forward stimulated Brillouin scattering (FSBS) attracted substantial attention for its ability to probe media surrounding optical fibers. Currently, all techniques extract the information from the FSBS-induced local energy transf ...

2021

Advanced methods for Brillouin based distributed optical fiber sensors

Simon Adrien Zaslawski

After more than thirty years of continuous research and development, the performances of conventional Brillouin based distributed optical fiber sensors (DOFS) are now peaking, as they are facing fundamental barriers that restrict the power of the light inj ...

EPFL2021

Helimagnons and Skyrmion Dynamics in Cu2OSeO3 and Fe/Gd Multilayers Explored by Brillouin Light Scattering and X-ray Microscopy

Ping Che

Spin dynamics in skyrmion hosting materials provide novel functionality in magnonics because of the formation of a novel magnon band structure and the nanoscale sizes of magnetic skyrmions. In this thesis, we explore the spin dynamics in the chiral magnet ...

EPFL2021

Magnons, worms and nanogratings in artificial magnetic quasicrystals

Sho Watanabe

Magnons (spin waves, SWs) are elementary spin excitations in magnetically ordered materials. They are the promising quanta for the transmission and processing of information. Magnons can be coupled to the electromagnetic waves utilized for the wireless com ...

EPFL2021

Opto-mechanical cross-talk reduction in air-holes multicore fibers

Luc Thévenaz, Zhisheng Yang, Simon Adrien Zaslawski, Yun Fu

We report on the use of air-holes in multicore fibers to alleviate intercore perturbations induced by forward stimulated Brillouin scattering. Comparisons with conventional multicore fibers show significant improvement in terms of cross-talk reduction. ...

Optical Society of America2020

Disorder‐Induced Signal Filtering with Topological Metamaterials

Romain Christophe Rémy Fleury, Farzad Zangeneh Nejad

Disorder, ubiquitously present in realistic structures, is generally thought to disturb the performance of analog wave devices, as it often causes strong multiple scattering effects that largely arrest wave transportation. Contrary to this general view, he ...

Wiley2020