Publications associées à Polarisation du spin

Orientation-dependent two-dimensional magnonic crystal modes in an ultralow-damping ferrimagnetic waveguide containing repositioned hexagonal lattices of Cu disks

Two-dimensional (2D) hexagonal lattices of Cu disks are shown to induce orientation-dependent magnonic crystal (MC) modes for propagating forward volume spin waves in a single-crystal yttrium iron garnet (YIG) film. The width and depth of the magnonic band ...

American Physical Society (APS)2024

Single Chip Dynamic Nuclear Polarization Microsystems

Nergiz Sahin Solmaz

Nuclear magnetic resonance (NMR) methods are powerful tools employed in many fields, including physics, chemistry, material science, biology, and medicine. The use of NMR methodologies in an even wider range of applications is often hindered by the relativ ...

EPFL2023

Long-Distance Coherent Propagation of High-Velocity Antiferromagnetic Spin Waves

Jean-Philippe Ansermet, Haiming Yu, Jilei Chen, Yao Zhang, Song Liu, Rundong Yuan, Cheng Song

We report on coherent propagation of antiferromagnetic (AFM) spin waves over a long distance (similar to 10 mu m) at room temperature in a canted AFM alpha-Fe2O3 owing to the Dzyaloshinskii-Moriya interaction (DMI). Unprecedented high group velocities (up ...

AMER PHYSICAL SOC2023

Periodic and Aperiodic NiFe Nanomagnet/Ferrimagnet Hybrid Structures for 2D Magnon Steering and Interferometry with High Extinction Ratio

Dirk Grundler, Sho Watanabe, Andrea Mucchietto, Shixuan Shan, Elif Nur Dayi, Vinayak Shantaram Bhat

Magnons, quanta of spin waves, are known to enable information processing with low power consumption at the nanoscale. So far, however, experimentally realized half-adders, wave-logic and binary output operations were based on few µm-long spin waves and re ...

Wiley2023

Structure, Spin Correlations, and Magnetism of the S=1/2 Square-Lattice Antiferromagnet Sr2CuTe1-xWxO6 (0 ≤ x ≤ 1)

Henrik Moodysson Rønnow, Ellen Fogh, Peter Babkevich, Sami Juhani Vasala

Quantum spin liquids are highly entangled magnetic states with exotic properties. The S = 1/2 square-lattice Heisenberg model is one of the foundational models in frustrated magnetism with a predicted, but never observed, quantum spin liquid state. Isostru ...

Amer Chemical Soc2023

Active Ferromagnetic Metasurface with Topologically Protected Spin Texture for Spectral Filters

Dirk Grundler, Haiming Yu, Jilei Chen

Electromagnetic metasurfaces modulate a material's response to electromagnetic waves by specifically arranged elements with dimensions below the wavelength. They have opened new fields of research, including flat optics and nanophotonics on a chip. Ferroma ...

2022

Hidden bulk and surface effects in the spin polarization of the nodal-line semimetal ZrSiTe

Marco Grioni, Arnaud Magrez, Oleg Yazyev, Daniel Gosalbez Martinez, Helmuth Berger, Alberto Crepaldi, Mauro Fanciulli, Gianmarco Gatti, Silvan Dino Marcos Roth

Local inversion symmetry breaking in centrosymmetric materials can lead to large spin polarization of the electronic band structure in separate sectors of the unit cell. Here, the authors reveal such hidden spin polarisation in ZrSiTe using spin and angle ...

NATURE RESEARCH2021

Crystal Field Effect and Electric Field Screening in Multilayer Graphene with and without Twist

Oleg Yazyev, Quansheng Wu

We address the intrinsic polarization and screening of an external electric field in a broad range of ordered and twisted configurations of multilayer graphene, using an ab initio approach combining density functional theory and the Wannier function formal ...

AMER CHEMICAL SOC2021

Ab Initio Electron-Phonon Interactions in Correlated Electron Systems

Nicola Marzari, Iurii Timrov, Matteo Cococcioni, Andrea Floris

Electron-phonon (e-ph) interactions are pervasive in condensed matter, governing phenomena such as transport, superconductivity, charge-density waves, polarons, and metal-insulator transitions. First-principles approaches enable accurate calculations of e- ...

AMER PHYSICAL SOC2021

A Low Power 35 GHz HEMT Oscillator for Electron Spin Resonance Spectroscopy

Giovanni Boero, Nergiz Sahin Solmaz, Alessandro Valentino Matheoud

This paper presents a low power microwave oscillator designed as sensor for electron spin resonance (ESR) spectroscopy. Low power consumption is necessary for low temperature operation. Additionally, lower power consumption allows for a lower microwave mag ...

IEEE2021

Direct observation of multiband transport in magnonic Penrose quasicrystals via broadband and phase-resolved spectroscopy

Dirk Grundler, Sho Watanabe, Mohammad Hamdi, Vinayak Shantaram Bhat, Korbinian Baumgärtl

Quasicrystals are aperiodically ordered structures with unconventional rotational symmetry. Their peculiar features have been explored in photonics to engineer bandgaps for light waves. Magnons (spin waves) are collective spin excitations in magnetically o ...

2021

Radial Spin Texture of the Weyl Fermions in Chiral Tellurium

Majed Chergui, Henrik Moodysson Rønnow, Marco Grioni, Oleg Yazyev, Luc Testa, Daniel Gosalbez Martinez, Michele Puppin, Philippe Bugnon, Luca Moreschini, Alberto Crepaldi, Mauro Fanciulli, Gianmarco Gatti, Simon Karl Moser, Edoardo Martino, Silvan Dino Marcos Roth, Serhii Polishchuk

Trigonal tellurium, a small-gap semiconductor with pronounced magneto-electric and magneto-optical responses, is among the simplest realizations of a chiral crystal. We have studied by spin- and angle-resolved photoelectron spectroscopy its unconventional ...

AMER PHYSICAL SOC2020

Spin-wave coupling to electromagnetic cavity fields in dysposium ferrite

Jean-Philippe Ansermet, Arnaud Magrez, Marcin Bialek

Coupling of spin waves with electromagnetic cavity field is demonstrated in an antiferromagnet, dysprosium ferrite (DyFeO3). By measuring transmission at 0.2-0.35 THz and sweeping sample temperature, magnon-photon coupling signatures were found at crossing ...

AMER PHYSICAL SOC2020

Improvement of Mott spin polarimeters: An overlooked redundancy

Mauro Fanciulli

In Mott polarimeters, the measurement of the spin polarization of an electron beam along two perpendicular quantization axes is commonly performed by collecting scattered electrons with four independent detectors placed azimuthally at 90 degrees from each ...

2020

Experimental observation of the acoustic Z2 Weyl semimetallic phase in synthetic dimensions

Romain Christophe Rémy Fleury, Farzad Zangeneh Nejad

Scalar waves such as airborne sound lack an intrinsic spin degree of freedom, making the realization of sonic Z2 topological phases based on spin degeneracy challenging. Here, we demonstrate the relevance of synthetic dimensions and higher-dimensional topo ...

2020

Weyl fermions, Fermi arcs, and minority-spin carriers in ferromagnetic CoS2

Samuel Thomas Stolz, Thorsten Schmitt, Vladimir N. Strocov, Timur Kim

Magnetic Weyl semimetals are a newly discovered class of topological materials that may serve as a platform for exotic phenomena, such as axion insulators or the quantum anomalous Hall effect. Here, we use angle-resolved photoelectron spectroscopy and ab i ...

2020

Experimental studies of the equilibrium and out-of-equilibrium electronic structure of non-symmorphic topological materials

Gianmarco Gatti

Symmetry and topology are fundamental properties of nature. Mathematics provides us with a general framework to understand these concepts. On one side, symmetry describes the invariance properties of an object for specific transformations. On the other sid ...

EPFL2020

Enhanced Intersystem Crossing and Transient Electron Spin Polarization in a Photoexcited Pentacene–Trityl Radical

David Lyndon Emsley, Jacques-Edouard Moser, Aaron James Rossini, Dominik Józef Kubicki, Etienne Christophe Socie, Moreno Lelli, Gabriele Stevanato, Claudia Esther Avalos

Identifying and characterizing systems that generate well-defined states with large electron spin polarization is of high interest for applications in molecular spintronics, high-energy physics, and magnetic resonance spectroscopy. The generation of electr ...

2020

Long-range magnetic ordering in Li2MnGeO4 and precursor short-range spin correlations

Irina Safiulina, Artem Korshunov

Long-range magnetic ordering and short-range spin correlations in layered noncentrosymmetric orthogermanate Li2MnGeO4 were studied by means of polarized and unpolarized neutron scattering. The combined Rietveld refinement of synchrotron and neutron powder ...

2020

Chiral Spin-Wave Velocities Induced by All-Garnet Interfacial Dzyaloshinskii-Moriya Interaction in Ultrathin Yttrium Iron Garnet Films

Dirk Grundler, Ping Che, Peng Gao, Haiming Yu, Yuehui Li, Sa Tu, Jilei Chen, Jianyu Zhang, Song Liu, Tao Liu

Spin waves can probe the Dzyaloshinskii-Moriya interaction (DMI), which gives rise to topological spin textures, such as skyrmions. However, the DMI has not yet been reported in yttrium iron garnet (YIG) with arguably the lowest damping for spin waves. In ...

2020