A5090091156- Magnetic properties of thin films
- Advanced X-ray Imaging Techniques
- Advanced Electron Microscopy Techniques and Applications
- Plasmonic and Surface Plasmon Research
- Terahertz technology and applications
- Photonic Crystals and Applications
- Magneto-Optical Properties and Applications
- Characterization and Applications of Magnetic Nanoparticles
- Metamaterials and Metasurfaces Applications
- Orbital Angular Momentum in Optics
- Theoretical and Computational Physics
- Spectroscopy and Quantum Chemical Studies
- Magnetic Properties and Applications
- Photonic and Optical Devices
- Topological Materials and Phenomena
- Particle Accelerators and Free-Electron Lasers
- Laser-Matter Interactions and Applications
- X-ray Spectroscopy and Fluorescence Analysis
- Laser-Plasma Interactions and Diagnostics
- Quantum and electron transport phenomena
- Mechanical and Optical Resonators
- Force Microscopy Techniques and Applications
- Magnetic and transport properties of perovskites and related materials
- Random lasers and scattering media
- Physics of Superconductivity and Magnetism
Elettra-Sincrotrone Trieste S.C.p.A.
2021-2024
Ca' Foscari University of Venice
2022-2024
Stockholm University
2017-2022
CIC nanoGUNE
2014-2019
Ayuntamiento de San Sebastián
2019
AlbaNova
2019
We propose a new strategy to search for dark matter axions using tunable cryogenic plasmas. Unlike current experiments, which repair the mismatch between axion and photon masses by breaking translational invariance (cavity dielectric haloscopes), plasma haloscope enables resonant conversion matching mass frequency. A key advantage is that frequency unrelated physical size of device, allowing large volumes. identify wire metamaterials as promising candidate plasma, wherein can be tuned...
Abstract The emergence of collective order in matter is among the most fundamental and intriguing phenomena physics. In recent years, dynamical control creation novel ordered states not accessible thermodynamic equilibrium receiving much attention 1–6 . theoretical concept multiferroicity has been introduced to describe magnetization due time-dependent electric polarization non-ferromagnetic materials 7,8 simple terms, coherent rotating motion ions a crystal induces magnetic moment along...
Electromagnetic waves possessing orbital angular momentum (OAM) are powerful tools for applications in optical communications, quantum technologies, and tweezers. Recently, they have attracted growing interest since can be harnessed to detect peculiar helical dichroic effects chiral molecular media magnetic nanostructures. In this work, we perform single-shot per position ptychography on a nanostructured object at seeded free-electron laser, using extreme ultraviolet OAM beams of different...
We present a novel concept of magnetically tunable plasmonic crystal based on the excitation Fano lattice surface modes in periodic arrays magnetic and optically anisotropic nanoantennas. show how coherent diffractive far-field coupling between elliptical nickel nanoantennas is governed by two in-plane, orthogonal spectrally detuned responses individual building block, one directly induced incident radiation other application an external field. The consequent field-induced leads to highly...
Enhancing magneto-optical effects is crucial for reducing the size of key photonic devices based on non-reciprocal propagation light and to enable active nanophotonics. Here, we disclose a currently unexplored approach that exploits hybridization with multipolar dark modes in specially designed magnetoplasmonic nanocavities achieve large enhancement magneto-optically induced modulation polarization. The broken geometrical symmetry design enables coupling free-space plasmonic ring...
We report on the experimental evidence of magnetic helicoidal dichroism, observed in interaction an extreme ultraviolet vortex beam carrying orbital angular momentum with a vortex. Numerical simulations based classical electromagnetic theory show that this dichroism is interference light modes different momenta, which are populated after between and topology. This observation gives insight into interplay magnetism sets framework for development new analytical tools to investigate ultrafast...
We have numerically solved the Landau-Lifshitz-Gilbert (LLG) equation in its standard and inertial forms to study magnetization switching dynamics a $3d$ thin film ferromagnet. The is triggered by ultrashort magnetic field pulses of varying width amplitude picosecond Tesla range. compared solutions two equations terms characteristic, speed energy analysis. Both return qualitatively similar dynamics, characterized regions slower precessional behavior faster ballistic motion. In case found 25...
Collective lattice dynamics determine essential aspects of condensed matter, such as elastic and thermal properties. These exhibit strong dependence on the length-scale, reflecting marked wavevector excitations. The extreme ultraviolet transient grating (EUV TG) approach has demonstrated potential accessing a range corresponding to 10s nm representing spatial scale highest relevance for fundamental physics forefront technology, previously inaccessible by optical TG other inelastic scattering...
The THz Kerr effect measures the birefringence induced in an otherwise isotropic material by a strong pulse driving Raman-active excitations of systems. Here we provide experimental evidence sizable response insulating ${\mathrm{SrTiO}}_{3}$ due to infrared-active lattice vibrations. Such signal, named ionic effect, is associated with simultaneous excitation multiple phonons. Thanks theoretical modeling time, polarization, and temperature dependence birefrengence, can disentangle from...
A novel approach to nanoactuation that relies on magnetomechanics instead of the conventional electromechanics utilized in micro and nanoactuated mechanical systems is devised demonstrated. Namely, magnetomechanical devices can change shape command using a remote magnetic external stimulus, with control at subnanometer scale are designed fabricated. In contrast electromechanical systems, activation does not require physical contacts. Remote have tremendous potential bringing vast...
Ultrafast control of magnetization on the nanometer length scale, in particular all-optical switching, is key to putting ultrafast magnetism path toward future technological application data storage technology. However, manipulation with light this scale challenging due wavelength limitations optical radiation. Here, we excite transient magnetic gratings a GdFe alloy periodicity 87 nm by interference two coherent femtosecond pulses extreme ultraviolet spectral range. The subsequent evolution...
A novel device is designed for on-chip selective trap and two-dimensional remote manipulation of single multiple fluid-borne magnetic particles using field controlled domain walls in circular nanostructures. The combination different ring-shaped nanostructures sequences allows with high-precision along any arbitrary pathway on a chip surface. As service to our authors readers, this journal provides supporting information supplied by the authors. Such materials are peer reviewed may be...
We utilize coherent femtosecond extreme ultraviolet (EUV) pulses derived from a free electron laser (FEL) to generate transient periodic magnetization patterns with periods as short 44 nm. Combining spatially excitation resonant probing at the dichroic M-edge of cobalt allows us create and probe gratings electronic magnetic excitations in CoGd alloy. In demagnetized sample, we observe an 50 fs rise time close FEL pulse duration ~0.5 ps decay within range for electron-phonon relaxation...
We present a comprehensive experimental and numerical study of magnetization dynamics in thin metallic film triggered by single-cycle terahertz pulses $\ensuremath{\sim}20\text{ }\text{ }\mathrm{MV}/\mathrm{m}$ electric field amplitude $\ensuremath{\sim}1\text{ }\mathrm{ps}$ duration. The is probed using the femtosecond magneto-optical Kerr effect, it reproduced numerically macrospin simulations. can be decomposed three distinct processes: coherent precession around magnetic field, an...
We investigate the role of domain walls in ultrafast magnon dynamics an antiferromagnetic NiO single crystal a pump-probe experiment with variable pump photon energy. Analysing amplitude energy-dependent photo-induced spin dynamics, we detect yet unreported coupling between material's characteristic THz- and GHz-magnon modes. explain this unexpected two orthogonal eigenstates corresponding Hamiltonian by modelling magneto-elastic interaction spins different domains. find that such...
Experimental characterization of the structural, electronic and dynamic properties dilute systems in aqueous solvents, such as nanoparticles, molecules proteins, are nowadays an open challenge. X-ray absorption spectroscopy (XAS) is probably one most established approaches to this aim it element-specific. However, typical interest often composed light elements that require extreme-ultraviolet soft photons. In spectral regime, water other solvents rather opaque, thus demanding radical...
All-optical switching (AOS) results in ultrafast and deterministic magnetization reversal upon single laser pulse excitation, potentially supporting faster more energy-efficient data storage. To explore the fundamental limits of achievable bit densities AOS, we have used soft X-ray transient grating spectroscopy to study magnetic response a GdFe alloy after spatially structured excitation with periodicity 17 nm. The spatial evolution combination atomistic spin dynamics microscopic...
Time-resolved ultrafast EUV magnetic scattering was used to test a recent prediction of >10 km/s domain wall speeds by optically exciting sample with nanoscale labyrinthine pattern. Ultrafast distortion the diffraction pattern observed at markedly different timescales compared magnetization quenching. The shows threshold dependence laser fluence, not seen for quenching, consistent picture motion pinning sites. Supported simulations, we show that speed ≈66 highly curved walls can explain...
We present a study of the compositional and temperature-dependent magnetic properties epitaxial CoCr thin films whose composition has bathtublike depth profile...
We describe the design of two types metamaterials aimed at enhancing terahertz field pulses that can be used to control magnetic state in condensed matter systems. The first structure is a so-called "dragonfly" antenna, able realize five-fold enhancement impinging field, while preserving its broadband features. For currently available state-of-the-art table top sources, this leads peak fields exceeding 1 T. second an octopole antenna circularly-polarized electric polarization state. obtain...
We report local field strength enhancement of single-cycle terahertz (THz) pulses in an ultrafast time-resolved x-ray diffraction experiment. show that patterning the sample with gold microstructures increases THz without changing pulse shape or drastically affecting quality pattern. find a five-fold increase THz-induced intensity change presence on SrTiO3 thin-film sample.
Ferromagnetic nanodiscs can exhibit an enhancement, of more than 100%, in their magneto-optical activity. This effect could be used nano-optical devices for communications, energy harvesting, and biosensors.