A5101568372- Magnetic properties of thin films
- Advanced Condensed Matter Physics
- Magnetic and transport properties of perovskites and related materials
- Magneto-Optical Properties and Applications
- Physics of Superconductivity and Magnetism
- Phase-change materials and chalcogenides
- Photonic and Optical Devices
- Theoretical and Computational Physics
- Magnetic Properties and Applications
- ZnO doping and properties
- Magnetic Bearings and Levitation Dynamics
- Laser-Matter Interactions and Applications
- Photonic Crystals and Applications
- Quantum and electron transport phenomena
- Electric Motor Design and Analysis
- Semiconductor Lasers and Optical Devices
- Multiferroics and related materials
- Advanced Photonic Communication Systems
- Sensorless Control of Electric Motors
- Advanced Memory and Neural Computing
- Surface and Thin Film Phenomena
- Surface Roughness and Optical Measurements
- Superconducting Materials and Applications
- Iron-based superconductors research
- Thermal Analysis in Power Transmission
Radboud University Nijmegen
2021-2025
Radboud Institute for Molecular Life Sciences
2021-2025
Radboud University Medical Center
2021-2025
Shanghai Institute for Science of Science
2025
Institute of Science Tokyo
2025
Tokyo Institute of Technology
2020-2024
Institute for Molecular Science
2023-2024
Kyoto University Institute for Chemical Research
2002-2020
Kyoto Bunkyo University
2013-2020
Kyoto University
2002-2020
The dense Kondo behaviour observed in Ce metal, its alloys and compounds is discussed by taking into account spin-orbit coupling crystal field splitting. Especially, using an expression for the temperature under a field, we clarify reason why effect donminates RKKY interaction.
Chiral spin textures of a ferromagnetic layer in contact to heavy non-magnetic metal, such as Néel-type domain walls and skyrmions, have been studied intensively because their potential for future nanomagnetic devices. The Dyzaloshinskii-Moriya interaction (DMI) is an essential phenomenon the formation chiral textures. In spite recent theoretical progress aiming at understanding microscopic origin DMI, experimental investigation unravelling physics stake still required. Here we...
The electric field (EF) effect on the magnetic domain structure of a Pt/Co system was studied, where an EF applied to top surface Co layer. width maze significantly modified by application at temperature slightly below Curie temperature. After detailed analysis, change in exchange stiffness induced suggested dominate modulation observed experiment. accumulation electrons layer resulted increase and result consistent with recent theoretical prediction.
The anomalous Nernst effect (ANE) generates electromotive forces transverse to temperature gradients and has attracted much attention for potential applications into novel thermoelectric power generators. ANE efficiency is generally characterized by uniform in a steady state prepared heaters. However, although focusing laser beams on magnetic film can form larger gradients, the irradiation method not been sufficiently considered quantifying coefficient due difficulty estimating localized...
This paper proposes a new initial rotor position estimation method of sensorless permanent magnet (PM) synchronous motor at starting condition, which has no sensitivity to the armature resistance. The is based on saliency and employs alternating magnetic field excited by current controller. phase differences between magnetizing references voltage make it possible estimate direction accurately without parameters, except ratio direct axis quadrature inductance. Also, pole evidently identified...
All-optical helicity dependent switching (AO-HDS), deterministic control of magnetization by circularly polarized laser pulses, allows to efficiently manipulate spins without the need a magnetic field. However, AO-HDS in ferromagnetic metals so far requires many pulses for fully their states. Using combination short, 90-fs linearly pulse and subsequent longer, 3-ps pulse, we demonstrate that number full reversal can be reduced 4 pairs single stack Pt/Co/Pt. The obtained results suggest...
In this study, we have investigated perpendicular magnetic anisotropy in a MgO/Co/Pt structure under an electric field. The change the interface energy MgO/Co stack upon application of gate voltage was determined by using transport measurement technique. result indicates that decrease electron number at surface Co layer leads to enhancement temperature sufficiently lower than Curie temperature.
Electric field effects on magnetism in metals have attracted widespread attention, but the microscopic mechanism is still controversial. We experimentally show relevancy between electric effect and electronic structure Pt a ferromagnetic state using element-specific measurements: x-ray magnetic circular dichroism (XMCD) absorption spectroscopy (XAS). fields are applied to surface of ultrathin metallic Pt, which moment induced by proximity resulting from Co underlayer. XMCD XAS measurements...
An X-ray tomographic technique was developed to investigate the internal magnetic domain structure in a micrometer-sized ferromagnetic sample. The is based on scanning hard nanoprobe using circular dichroism (XMCD). From transmission XMCD images at Gd L3 edge as function of sample rotation angle, three-dimensional (3D) distribution single component vector GdFeCo microdisc reconstructed with spatial resolution 360 nm, modified algebraic reconstruction algorithm. method applicable practical...
Abstract Since the first experimental observation of all-optical switching phenomena, intensive research has been focused on finding suitable magnetic systems that can be integrated as storage elements within spintronic devices and whose magnetization controlled through ultra-short single laser pulses. We report here atomistic spin simulations in multilayered structures alternating n monolayers Tb m Co. By using a two temperature model, we numerically calculate thermal variation each...
The diffusion of charged heavy particles in metals is discussed by the method density matrix, extending Kagan-Klinger theory to include electron-particle interaction. This can be applied both cases band-like and hopping-like diffusions. at low temperatures determined scattering overlap integral between two electron clouds situated different sites. extended system with partial wave components T-matrix each site.
We fabricated electric-field-effect transistor structures with a channel layer of an itinerant ferromagnet ${\mathrm{SrRuO}}_{3}$ (SRO) heterostructured cap ${\mathrm{BaTiO}}_{3}$ and investigated the electric field effects on anomalous Hall effect (AHE) in SRO. show that by applying positive negative gate voltages (${V}_{\mathrm{G}}$), conductivity SRO increases decreases, respectively, regardless its sign, while no change magnetic easy axis direction is observed. The results indicate...
We study the perpendicular magnetic anisotropy (PMA) of CoFeB/MgO bilayers in contact with W, Ta, IrMn and Ti which has been suggested as spin-orbit-torque-related underlayers. The saturation magnetization CoFeB depends on underlayer materials due to formation a dead-layer, affecting PMA strength each film. x-ray circular dichroism measurement reveals that interfacial intermixing suppresses only orbital moment Fe, while simultaneously both in-plane moments Co.
We performed time-resolved pump–probe measurements using rare-earth iron garnet Gd3/2Yb1/2BiFe5O12 as a two-sublattice ferrimagnet. measured the initial phases of magnetic resonance modes below and above magnetization compensation temperature to clarify sublattice selectivity inverse Faraday effect in ferrimagnets. A comparison time evolution estimated equations motion revealed that occurring ferrimagnetic materials has selectivity. This is striking contrast antiferromagnets, which acts on...
In this study, we investigated the magnetization response of polycrystalline magnetic garnet film for stress. The calculation suggests that balance anisotropic energy under field is an essential factor to modulate by We fabricated magnetophotonic crystal based voltage driven type magneto-optic spatial light modulator, and measured experimental results had a good agreement with our calculation. results, magnitude linearity modulation stress was depending on static bias field, stress,...
In this study, we have investigated magnetic domain wall motion under gate electric fields in a perpendicularly magnetized Co/Pt wire. The transparent electrode was directly monitored using magneto-optical Kerr effect microscope. velocity determined as function of temperature and voltage. It found that could be modulated by up to two orders magnitude changing the
Electric field effect on magnetism is an appealing technique for manipulating the magnetization at a low cost of energy. Here, we show that local ultra-thin Co film can be switched by just applying gate electric without assist any external magnetic or current flow. The switching explained nucleation and annihilation domain through wall motion induced field. Our results lead to free ultra-low energy spintronic applications.
A creep motion of the magnetic domain wall (DW) in a perpendicularly magnetized Co wire, where DW energy is artificially varied by applying sloped electric field, studied. Under field and constant external velocity gradually changes according to position wire owing spatially varying energy. Although can be source drive DW, no clear electric-field-induced observed, most likely because effective induced very small present system.
The Curie temperature TC is one of the most fundamental physical properties ferromagnetic materials and can be described by Weiss molecular field theory with exchange interaction neighboring atoms. Here, we demonstrate electrical control coupling in cobalt films through direct magnetization measurements. We find that reduction temperature, which caused thermal spin wave excitation scales Bloch's law, clearly depends on applied electric field. Furthermore, confirm correlation between...
Abstract The electric field control of superparamagnetism is realized using a Cu/Ni system, in which the deposited Ni shows superparamagnetic behavior above blocking temperature. An double-layer capacitor (EDLC) with electrode and nonmagnetic counter fabricated to examine effect on magnetism magnetic electrode. By changing voltage applied EDLC, temperature system clearly modulated.
Using diffraction of femtosecond laser pulses visible light by a magnetic domain pattern in an iron garnet, we demonstrate proof concept time-resolved measurements movements with nanometer spatial and temporal resolution. In this method, (pump) pulse initiates magnetization dynamics sample that is initially labyrinth state, while equally short linearly polarized (probe) diffracted the pattern. The components are orthogonally to incident generate several concentric rings. Nanometer small...