Spectral distribution of the fluctuations of the magnetization of a uniaxial ferromagnetic film that has been placed in a sinusoidal magnetic field

In the linear and planar motors, the 1D Halbach magnet array is extensively used. The sinusoidal property of the magnetic field deteriorates by analyzing the magnetic field at a small air gap. Therefore, a new 1D Halbach magnet array is proposed, in which the permanent magnet with a curved surface is applied. Based on the superposition of principle and Fourier series, the magnetic flux density distribution is derived. The optimized curved surface is obtained and fitted by a polynomial. The sinusoidal magnetic field is verified by comparing it with the magnetic flux density of the finite element model. Through the analysis of different dimensions of the permanent magnet array, the optimization result has good applicability. The force ripple can be significantly reduced by the new magnet array. The effect on the mass and air gap is investigated compared with a conventional magnet array with rectangular permanent magnets. In conclusion, the new magnet array design has the scalability to be extended to various sizes of motor and is especially suitable for small air gap applications.

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A 60-Hz sinusoidal magnetic field induces apoptosis of prostate cancer cells through reactive oxygen species

International Journal of Radiation Biology ◽

10.1080/09553000802460206 ◽

2008 ◽

Vol 84 (11) ◽

pp. 945-955 ◽

Cited By ~ 34

Author(s):

Eui Kwan Koh ◽

Byung-Kyu Ryu ◽

Dong-Young Jeong ◽

Iel-Soo Bang ◽

Myung Hee Nam ◽

...

Keyword(s):

Magnetic Field ◽

Prostate Cancer ◽

Reactive Oxygen Species ◽

Cancer Cells ◽

Reactive Oxygen ◽

Oxygen Species ◽

Prostate Cancer Cells ◽

Sinusoidal Magnetic Field

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Controllable field-free switching of perpendicular magnetization through bulk spin-orbit torque in symmetry-broken ferromagnetic films

Nature Communications ◽

10.1038/s41467-021-22819-4 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Xuejie Xie ◽

Xiaonan Zhao ◽

Yanan Dong ◽

Xianlin Qu ◽

Kun Zheng ◽

...

Keyword(s):

Magnetic Field ◽

Domain Walls ◽

Single Layer ◽

Ferromagnetic Film ◽

Effective Field ◽

Composition Gradient ◽

Spin Orbit ◽

Interlayer Exchange Coupling ◽

Magnetization Switching ◽

Perpendicular Magnetization

AbstractProgrammable magnetic field-free manipulation of perpendicular magnetization switching is essential for the development of ultralow-power spintronic devices. However, the magnetization in a centrosymmetric single-layer ferromagnetic film cannot be switched directly by passing an electrical current in itself. Here, we demonstrate a repeatable bulk spin-orbit torque (SOT) switching of the perpendicularly magnetized CoPt alloy single-layer films by introducing a composition gradient in the thickness direction to break the inversion symmetry. Experimental results reveal that the bulk SOT-induced effective field on the domain walls leads to the domain walls motion and magnetization switching. Moreover, magnetic field-free perpendicular magnetization switching caused by SOT and its switching polarity (clockwise or counterclockwise) can be reversibly controlled in the IrMn/Co/Ru/CoPt heterojunctions based on the exchange bias and interlayer exchange coupling. This unique composition gradient approach accompanied with electrically controllable SOT magnetization switching provides a promising strategy to access energy-efficient control of memory and logic devices.

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Influence of a 50 Hz Sinusoidal Magnetic Field on Sea Urchin Embryogenesis

Electricity and Magnetism in Biology and Medicine ◽

10.1007/978-1-4615-4867-6_129 ◽

1999 ◽

pp. 545-547 ◽

Cited By ~ 2

Author(s):

Olga Zeni ◽

Maria Rosaria Scarfì ◽

Marco Della Noce ◽

Francesco La Cara ◽

Ferdinando Bersani ◽

...

Keyword(s):

Magnetic Field ◽

Sea Urchin ◽

Sinusoidal Magnetic Field

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The Magnetoelectric Effect of a Ni0.3Zn0.62Cu0.08Fe2O4 - PbFe0.5Nb0.5O3 Multilayer Composite

Archives of Metallurgy and Materials ◽

10.2478/amm-2014-0169 ◽

2014 ◽

Vol 59 (3) ◽

pp. 1011-1015

Author(s):

P. Guzdek ◽

M. Sikora ◽

Ł. Góra ◽

Cz. Kapusta

Keyword(s):

Magnetic Field ◽

Magnetoelectric Effect ◽

Magnetic Hysteresis ◽

Tape Casting ◽

Casting Process ◽

Layered Composites ◽

Practical Applications ◽

Magnetoelectric Composite ◽

Sinusoidal Magnetic Field ◽

Magnetoelectric Coefficient

Abstract The magnetoelectric effect in multiferroic materials has been widely studied for its fundamental interest and practical applications. The magnetoelectric effect observed for single phase materials like Cr2O3, BiFeO3, and Pb(Fe0.5Nb0.5)O3 is usually small. A much larger effect can be obtained in composites consisting of magnetostrictive and piezoelectric phases. This paper investigates the magnetoelectric effect of a multilayer (laminated) structure consisting of 6 nickel ferrite and 7 PFN relaxor layers. It describes the synthesis and tape casting process for Ni0.3Zn0.62Cu0.08Fe2O4 ferrite and relaxor PbFe0.5Nb0.5O3 (PFN). Magnetic hysteresis, ZFC - FC curves and dependencies of magnetization versus temperature for PFN relaxor and magnetoelectric composite were measured with a vibrating sample magnetometer (VSM) in an applied magnetic field up to 85 kOe at a temperature range of 10 – 400 K. Magnetoelectric effect at room temperature was investigated as a function of a static magnetic field (0.3 - 6.5 kOe) and the frequency of sinusoidal magnetic field (0.01 - 6.5 kHz). At lower magnetic field, the magnetoelectric coefficient increases slightly before reaching a maximum and then decreases. The magnetoelectric coefficient aME increases continuously as the frequency is raised, although this increase is less pronounced in the 1-6.5 kHz range. Maximum values of the magnetoelectric coefficient attained for the layered composites exceed about 50 mV/(Oe cm).

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Sinusoidal magnetic field stimulates magnetosome formation and affects mamA, mms13, mms6, and magA expression in Magnetospirillum magneticum AMB-1

Canadian Journal of Microbiology ◽

10.1139/w08-095 ◽

2008 ◽

Vol 54 (12) ◽

pp. 1016-1022 ◽

Cited By ~ 1

Author(s):

Xiaoke Wang ◽

Likun Liang ◽

Tao Song ◽

Longfei Wu

Keyword(s):

Magnetic Field ◽

Geomagnetic Field ◽

Biomedical Applications ◽

Magnetic Particles ◽

Industrial Sector ◽

Magnetic Pole ◽

Variable Intensity ◽

New Approach ◽

Sinusoidal Magnetic Field ◽

Magnetospirillum Magneticum

Magnetic particles are currently one of the most important materials in the industrial sector, where they have been widely used for biotechnological and biomedical applications. To investigate the effects of the imposed magnetic field on biomineralization in Magnetospirillum magneticum AMB-1 and to suggest a new approach that enhances formation of magnetosomes, cultures inoculated with either magnetic or nonmagnetic precultures were incubated under a sinusoidal magnetic field or geomagnetic field. The results showed that the sinusoidal magnetic field up-regulated mms6 expression in the cultures inoculated with magnetic cells, and magA, mms6, and mamA expression in the cultures inoculated with nonmagnetic cells. The applied sinusoidal magnetic field could block cell division, which could contribute to a decrease in the OD600 values and an increase in the coefficient of magnetism values of the cultures, which could mean that the percentage of mature magnetosome-containing bacteria was increased. The linearity of magnetosome chains was affected, but the number of magnetic particles in cells was increased when a sinusoidal magnetic field was applied to the cultures. The results imply that the variable intensity and orientation of the sinusoidal magnetic field resulted in magnetic pole conversion in the newly forming magnetic particles, which could affect the formation of magnetic crystals and the arrangement of the adjacent magnetosome.

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Interaction of Tops of Domains in Metal Nano of the Film

Materials Science Forum ◽

10.4028/www.scientific.net/msf.945.771 ◽

2019 ◽

Vol 945 ◽

pp. 771-775 ◽

Cited By ~ 14

Author(s):

V.P. Panaetov ◽

Denis B. Solovev

Keyword(s):

Magnetic Field ◽

Experimental Data ◽

Film Thickness ◽

Magnetic Structure ◽

Domain Walls ◽

Magnetic Moments ◽

Ferromagnetic Film ◽

Easy Magnetization ◽

Electron Transmission ◽

Transmission Microscope

Ferromagnetic film can be a matrix for recording information with the help of magnetic moments of electrons. The study of the processes of changing the magnetic structure in an electron-transmission microscope makes it possible to investigate micro magnetic phenomena. In this paper, we investigate the interaction between the vertices of neighboring regions. It is shown how the magnetic structure of the vertices of the domains changes as they approach each other with the help of an increasing constant magnetic field applied along the axis of easy magnetization. The distance was measured between the vertices of the domains. The schemes of distribution of the magnetization vectors between interacting vertices are shown. These schemes are made from experimental images of the magnetic structure. The distances between domain vertices and domain walls were compared on the basis of experimental data. The film thickness is 50 nm; the structure is Ni0.83-Fe0.17. The films were obtained by the method proposed by us. From the experimental results it follows that the interaction of the domain walls is observed at a distance of 20 microns and the interaction of the domain vertices is manifested at a distance of 100 μm.

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