A5048501435- Magnetic properties of thin films
- Magnetic Properties of Alloys
- Magnetic Properties and Applications
- Magnetic and transport properties of perovskites and related materials
- Rare-earth and actinide compounds
- Physics of Superconductivity and Magnetism
- Force Microscopy Techniques and Applications
- Theoretical and Computational Physics
- Characterization and Applications of Magnetic Nanoparticles
- Anodic Oxide Films and Nanostructures
- Mass Spectrometry Techniques and Applications
- Analytical Chemistry and Chromatography
- Metallurgical and Alloy Processes
- Nanoporous metals and alloys
- Hydrogen Storage and Materials
- Metal and Thin Film Mechanics
- Metallic Glasses and Amorphous Alloys
- Iron-based superconductors research
- Superconducting Materials and Applications
- Quantum and electron transport phenomena
- Surface and Thin Film Phenomena
- Diamond and Carbon-based Materials Research
- Advanced Measurement and Metrology Techniques
- Magnetic Properties and Synthesis of Ferrites
- Electronic and Structural Properties of Oxides
Leibniz Institute for Solid State and Materials Research
2015-2024
TU Dresden
2010-2019
National Physical Laboratory
2018
Institute of Physics
2018
Chinese Academy of Sciences
2018
Lanzhou University
2018
King Abdullah University of Science and Technology
2018
Lehman College
2018
City University of New York
2018
BASF (Germany)
2016
Since it was first demonstrated in 1987, magnetic force microscopy (MFM) has become a truly widespread and commonly used characterization technique that been applied to variety of research industrial applications. Some the main advantages method includes its high spatial resolution (typically ∼50 nm), ability work variable temperature fields, versatility, simplicity operation, all without almost any need for sample preparation. However, most commercial systems, historically provided only...
Here we present a combined study of the slightly underdoped novel pnictide superconductor Ba1-xKxFe2As2 by means x-ray powder diffraction, neutron scattering, muon-spin rotation (microSR), and magnetic force microscopy (MFM). Static antiferromagnetic order sets in below T{m} approximately 70 K as inferred from scattering zero-field-microSR data. Transverse-field microSR Tc shows coexistence magnetically ordered nonmagnetic states, which is also confirmed MFM imaging. We explain such...
Magnetic skyrmions are topologically protected nanoscale spin textures exhibiting fascinating physical behaviors. Recent observations of room temperature in sputtered multilayer films an important step towards their use ultra-low power devices. Such practical applications prefer to be stable at zero magnetic fields and temperature. Here, we report the creation skyrmion lattices Pt/Co/Ta multilayers by a scanning local field using force microscopy tips. We also show that those newly created...
High spatial resolution magnetic x-ray spectromicroscopy at photon energies near the cobalt L3 resonance was applied to probe an amorphous 50 nm thin SmCo5 film prepared by off-axis pulsed laser deposition onto transparent 200 Si3N4 membrane. Alternating gradient magnetometry shows a strong in-plane anisotropy and only weak perpendicular anisotropy, which is confirmed transmission soft microscopy images showing over field of view 10 μm primarily stripe-like domain pattern but with local...
Abstract Considering the growing interest in magnetic materials for unconventional computing, data storage, and sensor applications, there is active research not only on material synthesis but also characterisation of their properties. In addition to structural integral characterisations, imaging magnetisation patterns, current distributions fields at nano- microscale major importance understand responses qualify them specific applications. this roadmap, we aim cover a broad portfolio...
Abstract Modification of the magnetic properties under induced strain and curvature is a promising avenue to build three-dimensional devices, based on domain wall motion. So far, most studies with 3D structures were performed in helixes nanowires, mainly stationary walls. In this study, we demonstrate impact geometry, current-induced motion spin-orbital torque efficiency heterostructure, realized via self-assembly rolling technique polymeric platform. We introduce complete memory unit write,...
In order to enhance the energy density (BH)max as a key property for permanent magnet applications, exchanged-coupled trilayers of SmCo5/Fe/SmCo5 with fixed SmCo5 layer thicknesses (25 nm) and varying soft magnetic Fe film thickness have been epitaxially grown by pulsed laser deposition on Cr buffered MgO(110) substrates. The effect increasing reversal mechanism improved remanence due higher Fe-volume fraction was investigated vibrating sample magnetometry in external fields up 9 T. As...
Exchange coupled hard/soft magnetic nanocomposites have long been in the interest of research for improving energy density currently best hard materials such as Nd <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> Fe xmlns:xlink="http://www.w3.org/1999/xlink">14</sub> B (512 kJ/m <sup xmlns:xlink="http://www.w3.org/1999/xlink">3</sup> ) or SmCo xmlns:xlink="http://www.w3.org/1999/xlink">5</sub> (230 ). However, to compete with a well...
An approach is presented that allows quantifying the three dimensional magnetization pattern of a magnetic nanoobject from measured two Magnetic Force Microscopy (MFM) data. This based on MFM deconvolution approach, which quantitatively determines effective surface charges, micromagnetic calculation total charges at and below sample surface, projection lower lying onto for comparison such obtained with experimentally determined ones. Thus, by making use depth sensitivity applying...
Abstract The chemical functionalization of fullerene single molecule magnet Tb 2 @C 80 (CH Ph) enables the facile preparation robust monolayers on graphene and highly oriented pyrolytic graphite from solution without impairing their magnetic properties. Monolayers endohedral functionalized with pyrene exhibit bistability up to a temperature 28 K. use terminated linker molecules opens way devise integration spin carrying units encapsulated by cages graphitic substrates, be it single‐molecule...
Electrochemical deposition in magnetic field gradients is a promising method to synthesize structured deposits by exploiting the gradient force. Typically, templates with dimensions millimeter range are used, but downscaling desirable from fundamental and application points of view. In present study, pulse reverse plating copper performed combination four successively downscaled templates, which consist three iron wires diameters 1 mm, 500 µm, 250 125 µm. Structuring effects demonstrated for...
Epitaxial hcp cobalt films with pronounced $c$-axis texture have been prepared by pulsed lased deposition either directly onto ${\text{Al}}_{2}{\text{O}}_{3}(0001)$ single-crystal substrates or an intermediate ruthenium buffer layer. The crystal structure and epitaxial growth relation was studied x-ray diffraction, pole figure measurements, reciprocal-space mapping. Detailed vibrating-sample magnetometer analysis shows that the perpendicular anisotropy of these highly textured Co reaches...
We present a direct experimental investigation of the thermal ordering in an artificial analogue asymmetric two-dimensional Ising system composed rectangular array nano-fabricated magnetostatically interacting islands. During fabrication and below critical thickness magnetic material islands are thermally fluctuating thus is able to explore its phase space. Above freeze-in resulting arrested thermalized state for array. Determining we demonstrate genuine which can be analyzed context nearest...
Abstract Magnetic force microscopy (MFM) is a scanning technique that commonly employed to probe the sample’s magnetostatic stray fields via their interaction with magnetic tip. In this work, quantitative, single-pass MFM presented maps one stray-field component and its spatial derivative at same time. This uses special cantilever design high-aspect-ratio tip approximates monopole-like moment. Experimental details, such as control scheme, sensor design, which enables simultaneous gradient...
The magnetization reversal mechanism in pulsed laser deposited, hard magnetic epitaxial $\mathrm{Sm}{\mathrm{Co}}_{5}$ thin films with high coercivity $(>3\phantom{\rule{0.3em}{0ex}}\mathrm{T})$ and remanent polarization $(0.94\phantom{\rule{0.3em}{0ex}}\mathrm{T})$ is investigated. From temperature angle dependent hysteresis measurements the framework of micromagnetic model, we show that described by a hindered domain wall movement. This conclusion from global analysis supported force...
The disordered flux line lattice in single crystals of the slightly overdoped ${\text{BaFe}}_{2\ensuremath{-}x}{\text{Co}}_{x}{\text{As}}_{2}$ ($x=0.19$, ${T}_{\text{c}}=23\text{ }\text{K}$) superconductor is studied by magnetization measurements, small-angle neutron scattering, and magnetic force microscopy (MFM). In whole range fields up to 9 T, vortex pinning precludes formation an ordered Abrikosov lattice. Instead, a vitreous phase (vortex glass) with short-range hexagonal order...
A hot-deformed Nd-Fe-B sample has been chosen for the investigation of interaction domains by means magnetic force microscopy. During imaging process, a field up to 6 T was applied in situ along easy axis magnetization. The thermally demagnetized state presents regular pattern with an average width about 1 μm but much larger length scale. Starting from state, magnetization initial curve occurs via sequential switching neighboring grain columns at peripheries domains. Demagnetization...
Chemically ordered and highly textured L10 FePt-C granular films are potential media for future heat-assisted magnetic recording. Vibrating sample magnetometry of such in fields up to 14 T reveals a perpendicular coercivity μ0HC=4.92 an anisotropy field μ0HA=9.2 T, which translates (uni-axial) constant as high KU=5.3 MJ/m3. An analysis the remanent magnetization demagnetization curves shows that spatially separated FePt nanoparticles act Stoner-Wohlfarth ensemble uni-axial nanomagnets with...
Thin Nd-Fe-B films have been prepared by pulsed laser deposition on sapphire substrates. A Ta buffer layer has used to promote epitaxial growth. The temperature varied between 400 \ifmmode^\circ\else\textdegree\fi{}C and 700 proved be an important parameter for both, the phase formation control of microstructure coercivity. For low temperatures grow in small grains with irregular shape, generally observed $c$-axis texture is not fully developed. coercivity reaches values around 1.6 T. medium...
Epitaxial SmCo5 thin films with strong perpendicular magnetic anisotropy have been developed by pulsed laser deposition on heated Ru buffered Al2O3(0001) substrates. Pole figure measurements thicker reveal the existence of two epitaxial variants, 30° in-plane rotated to each other, which reduces a single relation for smaller film thickness. The presence phase direction c-axis is established multiple peak analysis x-ray data in pole geometry and confirmed numerical fit hysteresis...
The magnetization process of antiferromagnetically coupled ${[{(\text{Co}/\text{Pt})}_{8}/\text{Co}/\text{Ru}]}_{18}$ multilayers with perpendicular anisotropy is investigated via magnetic force microscopy at room temperature by imaging the domain configuration in fields. In zero-field state, due to anisotropy, stripe domains characteristic for ferromagnetic coupling are observed. By increasing external field, first modifies gradually, then transforms from continuous into isolated stripes,...
Films of Sm–Co have been sputtered on heated polycrystalline Al2O3 substrates. The effect variations the Sm content microstructure and hard magnetic properties was studied for otherwise constant process parameters. As generally observed, samples possess a texture where easy magnetization directions grains lay preferably in film plane. For lower TbCu7-type structure is stabilized higher CaCu5-type stabilized. crossover occurs around 17 at. %. Consistent with changes intrinsic properties,...