Composition Regulation and Microstructure Characterization of Fe100-xGax Films in the Manufacturing Industry

Fe100-xGax giant magnetostrictive films (GMF) are attracting ever increasing attention for their potential application to manufacturing integrated magnetostrictive displacement sensors. However, it is difficult to fabricate Fe100-xGax thin films with different compositions at will. The influence of compositions on alloy phases, grain sizes, film surface roughness, and magnetic domains of the films and magnetization of magnetron sputtered Fe100-xGax films was investigated. Changing the ratio of the pure iron slice areas to alloy target areas, the desired film composition was achieved by the improved Mosaic method. The morphologies, magnetic domain structure, microstructure, and compositions of Fe100-xGax films revealed by SEM, EDS, XRD, MFM, VSM, and TEM. The results show that there are <1 1 0 > texture in magnetron sputtered Fe100-xGax films. The sharp peak attributed to the A2 microstructure suggests that the film is crystalline. The magnetic domain structure of Fe100-xGax films presents a network form, and the domain width decreases with the decrease of gallium content. It is also found that the magnetic domains of the films are not uniform. The TEM result shows that there are some strip patterns in the films, and the diffraction ring is discontinuous because of the structure extinction. For a suitable candidate of microdevice applications in MEMS, the optimum composition film should be Fe83.25Ga16.75 film.

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Magnetic domains and domain wall pinning in two-dimensional ferromagnets revealed by nanoscale imaging

10.21203/rs.3.rs-78858/v1 ◽

2020 ◽

Author(s):

Qi-Chao Sun ◽

Tiancheng Song ◽

Eric Anderson ◽

Tetyana Shalomayeva ◽

Johannes Förster ◽

...

Keyword(s):

Domain Structure ◽

Spatial Resolution ◽

Magnetic Domain ◽

Magnetic Domain Structure ◽

Nitrogen Vacancy ◽

Two Dimensional ◽

Magnetic Domains ◽

Pinning Effect ◽

Nitrogen Vacancy Center ◽

Vacancy Center

Abstract Magnetic-domain structure and dynamics play an important role in understanding and controlling the magnetic properties of two-dimensional magnets, which are of interest to both fundamental studies and applications. However, the probe methods based on the spin-dependent optical permeability and electrical conductivity can neither provide quantitative information of the magnetization nor achieve nanoscale spatial resolution. These capabilities are essential to image and understand the rich properties of magnetic domains. Here, we employ cryogenic scanning magnetometry using a single-electron spin of a nitrogen-vacancy center in a diamond probe to unambiguously prove the existence of magnetic domains and study their dynamics in atomically thin CrBr3. The high spatial resolution of this technique enables imaging of magnetic domains and allows to resolve domain walls pinned by defects. By controlling the magnetic domain evolution as a function of magnetic field, we find that the pinning effect is a dominant coercivity mechanism with a saturation magnetization of about 26μB/nm2 for bilayer CrBr3. The magnetic-domain structure and pinning-effect dominated domain reversal process are verified by micromagnetic simulation. Our work highlights scanning nitrogen-vacancy center magnetometry as a quantitative probe to explore two-dimensional magnetism at the nanoscale.

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Correlation between the magnetic-microstructure and microwave mitigation ability of MxCo(1−x)Fe2O4 based ferrite–carbon black/PVA composites

Physical Chemistry Chemical Physics ◽

10.1039/c8cp05235b ◽

2018 ◽

Vol 20 (41) ◽

pp. 26431-26442 ◽

Cited By ~ 4

Author(s):

Gopal Datt ◽

Chetan Kotabage ◽

Suwarna Datar ◽

Ashutosh C. Abhyankar

Keyword(s):

Carbon Black ◽

Domain Structure ◽

Crucial Role ◽

Magnetic Domain ◽

Magnetic Domain Structure ◽

Magnetic Losses ◽

Magnetic Domains ◽

Magnetic Microstructure

This work reports on the correlation between the magnetic-domain structure and microwave mitigation properties of ferrite–Carbon black/PVA Composites. Distorted co-ordination of Fe3+ along with unique single axis oriented magnetic domains plays a crucial role in magnetic losses and hence, in mitigation of microwaves.

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Magnetostrictive Property and Magnetic Domain Structure of Fe-Ga Alloy Single Crystal under Tensile Strain

Materials Science Forum ◽

10.4028/www.scientific.net/msf.941.914 ◽

2018 ◽

Vol 941 ◽

pp. 914-918 ◽

Cited By ~ 2

Author(s):

Shun Fujieda ◽

Shimpei Asano ◽

Shunichiro Hashi ◽

Kazushi Ishiyama ◽

Tsuguo Fukuda ◽

...

Keyword(s):

Single Crystal ◽

Domain Structure ◽

Tensile Strain ◽

Complex Structure ◽

Magnetic Domain ◽

Magnetic Domain Structure ◽

Alloy Single Crystal ◽

Magnetic Domains ◽

Magnetization Direction ◽

Tensile Direction

The saturation value of the magnetostriction curve in the [100] direction of a Fe-Ga alloy single crystal was decreased from 226 to 55 ppm by applying the tensile strain of 533 ppm to the measured direction. By magnetic domain observation using a magneto-optic Kerr effect microscope, a complex structure composed of various magnetic domains was observed under zero applied strain. On the other hand, a stripe structure composed of magnetic domains with the magnetization direction in two kinds of <100> magnetic easy directions parallel to the tensile direction, which were separated by straight 180° domain walls, was observed under the tensile strain of 533 ppm. The characteristic magnetic domain structure due to the tensile strain was successfully observed as a cause of the significant decrease of the saturation value of the magnetostriction curve.

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Characterization of Microstructure and Magnetic Domain Structure in Sm-Co Based Permanent Magnets by Advanced Transmission Electron Microscopy

Journal of the Japan Institute of Metals and Materials ◽

10.2320/jinstmet1952.63.4_542 ◽

1999 ◽

Vol 63 (4) ◽

pp. 542-548 ◽

Cited By ~ 1

Author(s):

Jun-Mo Yang ◽

Daisuke Shindo ◽

Masaki Takeguchi ◽

Masahiro Kawasaki ◽

Tetsuo Oikawa

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Domain Structure ◽

Permanent Magnets ◽

Magnetic Domain ◽

Magnetic Domain Structure ◽

Transmission Electron

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Domains and domain nucleation in magnetron-sputtered CoCr thin films

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100151064 ◽

1993 ◽

Vol 51 ◽

pp. 1046-1047

Author(s):

B. G. Demczyk

Keyword(s):

Thin Films ◽

Domain Structure ◽

Magnetic Domain ◽

Domain Size ◽

Film Plane ◽

Magnetic Domain Structure ◽

Perpendicular Magnetization ◽

Columnar Grains ◽

Reversal Mechanism ◽

Lorentz Transmission Electron Microscopy

CoCr thin films have been of interest for a number of years due to their strong perpendicular anisotropy, favoring magnetization normal to the film plane. The microstructure and magnetic properties of CoCr films prepared by both rf and magnetron sputtering have been examined in detail. By comparison, however, relatively few systematic studies of the magnetic domain structure and its relation to the observed film microstructure have been reported. In addition, questions still remain as to the operative magnetization reversal mechanism in different film thickness regimes. In this work, the magnetic domain structure in magnetron sputtered Co-22 at.%Cr thin films of known microstructure were examined by Lorentz transmission electron microscopy. Additionally, domain nucleation studies were undertaken via in-situ heating experiments.It was found that the 50 nm thick films, which are comprised of columnar grains, display a “dot” type domain configuration (Figure 1d), characteristic of a perpendicular magnetization. The domain size was found to be on the order of a few structural columns in diameter.

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