Articles de revues : « Magnetic anisotrophy »

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Hartmann, Tue, Sanne Vandborg, Raben Rosenberg, Leif Sørensen et Poul Videbech. « Increased fractional anisotropy in cerebellum in obsessive–compulsive disorder ». Acta Neuropsychiatrica 28, n^o 3 (2 novembre 2015) : 141–48. http://dx.doi.org/10.1017/neu.2015.57.

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BackgroundPrevious morphology and diffusion-imaging studies have suggested that structural changes in white matter is an important part of the pathophysiology of obsessive–compulsive disorder (OCD). However, different methodological approaches and the heterogeneity of patient samples question the validity of the findings.Materials and methodsIn total, 30 patients were matched for age and sex with 30 healthy controls. All participants underwent T1-weighted magnetic resonance imaging, diffusion tensor imaging and T2 fluid-attenuated inversion recovery. Voxel-based morphometry and tract-based spatial statistics were used to compare white matter volumes and diffusion tensor imaging between groups. These data were analysed correcting for the effects of multiple comparisons, age, sex, severity and duration of illness as nuisance covariates. White matter hyperintensities were manually identified.ResultsIncrease in fractional anisotropy in cerebellum was the most prominent result. A decrease in fractional anisotrophy in patients comparable with previous studies was located in forceps minor. There were no differences in the white matter morphology or in the white matter hyperintensities between patients and healthy controls.ConclusionDecrease in fractional anisotrophy in forceps minor and increase in cerebellum were found, and they were not due to neither white matter hyperintensities nor morphology of the white matter. Cerebellar hyperconnectivity could be an important part of OCD pathophysiology.

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Soinski, M. « The anisotrophy of coercive force in cold-rolled goss-texture electrical sheets ». IEEE Transactions on Magnetics 23, n^o 6 (novembre 1987) : 3878–81. http://dx.doi.org/10.1109/tmag.1987.1065769.

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Rongkonusa, Melisa, Gerald Tamuntuan et Guntur Pasau. « Analisis Anisotropi Suseptibilitas Magnetik Batuan Beku Lengan Utara Sulawesi ». Jurnal MIPA 6, n^o 1 (2 mai 2017) : 8. http://dx.doi.org/10.35799/jm.6.1.2017.15846.

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Telah dilakukan penelitian untuk menentukan pola anisotropi suseptibilitas magnetik dan status singkapan batuan beku dari pola yang diperoleh. Pengukuran anisotropi suseptibilitas magnetic dilakukan pada lima sampel batuan beku dari Sulawesi Utara menggunakan Bartington MS2B. Arah pengukuran sampel disesuaikan dengan desain Tauxe. Hasilnya menunjukkan bahwa suseptibilitas maksimum terdistribusi disekitar arah utara dan timur. Sedangkan suseptibilitas intermediet dan minimum terdistribusi disekitar Utara-Timur dan Timur-Selatan. Elipsoida suseptibilitas cenderung prolate atau lebih lonjong. Batuan beku yang dianalisis merupakan kelompok batuan terobosan yang mekanisme lelehannya terjadi secara vertikal.A research has been conducted to determine the anisotropic pattern of magnetic susceptibility and the status of igneous rocks exposure from the obtained pattern. We have measured the anisotropy of magnetic susceptibility on five samples of igneous rock from North Sulawesi by Bartington MS2B. The position of samples were adjusted according to the Tauxe’s design. The result shows that the maximum susceptibility is distributed around northward and eastward, while the intermediate and minimum susceptibility are distributed around nortward-eastward and eastward-southward. The susceptibility ellipsoid tends to be prolate or more oval. This shows that the igneous rocks that have been analyzed are group of intrusive rocks which melting mechanism occurs through vertical fracture.enetie

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Nauman, Muhammad, Tayyaba Hussain, Joonyoung Choi, Nara Lee, Young Jai Choi, Woun Kang et Younjung Jo. « Low-field magnetic anisotropy of Sr₂IrO₄ ». Journal of Physics : Condensed Matter 34, n^o 13 (20 janvier 2022) : 135802. http://dx.doi.org/10.1088/1361-648x/ac484d.

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Abstract Magnetic anisotropy in strontium iridate (Sr2IrO4) is essential because of its strong spin–orbit coupling and crystal field effect. In this paper, we present a detailed mapping of the out-of-plane (OOP) magnetic anisotropy in Sr2IrO4 for different sample orientations using torque magnetometry measurements in the low-magnetic-field region before the isospins are completely ordered. Dominant in-plane anisotropy was identified at low fields, confirming the b axis as an easy magnetization axis. Based on the fitting analysis of the strong uniaxial magnetic anisotropy, we observed that the main anisotropic effect arises from a spin–orbit-coupled magnetic exchange interaction affecting the OOP interaction. The effect of interlayer exchange interaction results in additional anisotropic terms owing to the tilting of the isospins. The results are relevant for understanding OOP magnetic anisotropy and provide a new way to analyze the effects of spin–orbit-coupling and interlayer magnetic exchange interactions. This study provides insight into the understanding of bulk magnetic, magnetotransport, and spintronic behavior on Sr2IrO4 for future studies.

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Maniur, Rafael F., Adam Badra Cahaya et Azwar Manaf. « Law of Approach to Saturation for Determining Magnetic Intrinsic Behavior of BaFe12-xMnx/2Tix/2O19 and SrFe12-xMnx/2Tix/2O19 ». Al-Fiziya : Journal of Materials Science, Geophysics, Instrumentation and Theoretical Physics 4, n^o 2 (5 janvier 2022) : 78–82. http://dx.doi.org/10.15408/fiziya.v4i2.22206.

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The problem with permanent magnetic materials of very high anisotropic fields is that it is still difficult to determine the intrinsic magnetic properties, when measured using a magnetometer which has a limited magnetic field. The Law of Approach to Saturation (LAS) mathematical model provides a way to measure permanent magnets, with high anisotropic fields by correcting the magnetization data of the first quadrant curve or the virgin curve of the minor hysteresis loop. In this research, a computational LAS program was conducted to compute the intrinsic magnetic properties of magnetic materials, such as saturation magnetization, anisotropy field and magnetocrystalline anisotropy constant. Magnetization data were obtained from permagraph measurements of barium hexaferrite (BaFe12O19), strontium hexaferrite (SrFe12O19) and microwave absorbers BaFe12-xMnx/2Tix/2O19 and SrFe12-xMnx/2Tix/2O19. The convergences of magnetization were assessed to determine the effect of substitution on barium hexaferrite and strontium hexaferrite materials on saturation magnetization values, anisotropy constants and anisotropic fields.

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Deb, Debabrata, Banibrata Mukhopadhyay et Fridolin Weber. « Effects of Anisotropy on Strongly Magnetized Neutron and Strange Quark Stars in General Relativity ». Astrophysical Journal 922, n^o 2 (26 novembre 2021) : 149. http://dx.doi.org/10.3847/1538-4357/ac222a.

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Abstract We investigate the properties of anisotropic, spherically symmetric compact stars, especially neutron stars (NSs) and strange quark stars (SQSs), made of strongly magnetized matter. The NSs are described by the SLy equation of state (EOS) and the SQSs by an EOS based on the MIT Bag model. The stellar models are based on an a priori assumed density dependence of the magnetic field and thus anisotropy. Our study shows that not only the presence of a strong magnetic field and anisotropy, but also the orientation of the magnetic field itself, have an important influence on the physical properties of stars. Two possible magnetic field orientations are considered: a radial orientation where the local magnetic fields point in the radial direction, and a transverse orientation, where the local magnetic fields are perpendicular to the radial direction. Interestingly, we find that for a transverse orientation of the magnetic field, the stars become more massive with increasing anisotropy and magnetic-field strength and increase in size since the repulsive, effective anisotropic force increases in this case. In the case of a radially oriented magnetic field, however, the masses and radii of the stars decrease with increasing magnetic-field strength because of the decreasing effective anisotropic force. Importantly, we also show that in order to achieve hydrostatic equilibrium configurations of magnetized matter, it is essential to account for both the local anisotropy effects as well as the anisotropy effects caused by a strong magnetic field. Otherwise, hydrostatic equilibrium is not achieved for magnetized stellar models.

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HU, AI-YUAN, et YUAN CHEN. « TWO-DIMENSIONAL ANISOTROPIC HEISENBERG FERROMAGNET IN COEXISTING TRANSVERSE AND LONGITUDINAL MAGNETIC FIELDS ». International Journal of Modern Physics B 21, n^o 22 (10 septembre 2007) : 3877–87. http://dx.doi.org/10.1142/s0217979207037879.

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The two-dimensional spin-1/2 anisotropic Heisenberg ferromagnet is investigated in coexisting transverse and longitudinal magnetic fields. Using the Green function treatment, the magnetization and susceptibility are studied as a function of temperature, anisotropy and magnetic fields. The effects of exchange anisotropy and transverse magnetic field on the magnetic properties of the system are discussed.

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KRAUS, L. « LOCAL MAGNETIC ANISOTROPY AND MAGNETOANELASTIC EFFECT IN AMORPHOUS AND NANOCRYSTALLINE ALLOYS ». International Journal of Modern Physics B 07, n^o 01n03 (janvier 1993) : 916–21. http://dx.doi.org/10.1142/s0217979293001979.

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Anelastic deformation of amorphous and nanocrystalline metals results in an anisotropic distribution of atomic pair bonds. This mechanism can lead to rather strong macroscopic magnetic anisotropy in some alloys. Experimental results show that the creep-induced magnetic anisotropy of amorphous and nanocrystalline Fe- and Co-based alloys essentially depends both on TM and metalloid elements. This is a clear evidence that the random local magnetic anisotropy in these materials is closely related to the details of electronic structure. Based on this conclusion a model of bond -orientational anisotropy taking into account the distribution of local anisotropies in TM-based alloys is proposed.

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Min'kova, A. V., V. V. Prudnikov et P. V. Prudnikov. « Issledovanie vliyaniya effektov konkurentsii razlichnykh tipov anizotropii na kriticheskoe povedenie mul'tisloynykh magnitnykh struktur ». Журнал экспериментальной и теоретической физики 164, n^o 5 (15 décembre 2023) : 782–89. http://dx.doi.org/10.31857/s0044451023110081.

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The influence of the competition of single-ion anisotropy and easy-plane anisotropy on the magnetic properties of the multilayer structure Co/Cu/Co is investigated. The peculiarities of the influence of anisotropy effects are revealed both in the vicinity of critical temperature Tc and in the low-temperature range T Tc. The magnetic properties of the multilayer structure are numerically simulated using the anisotropic Heisenberg model. In the vicinity of Tc, easy-plane anisotropy is shown to exert a predominant influence on the magnetic properties of the structure as compared to the influence of single-ion anisotropy. In the low-temperature range, the switching of the magnetic state of the ferromagnetic film in an external field leads to the appearance of specific features in hysteresis effects due to the competition of two types of magnetic anisotropy. The magnetic structure exhibits a size-induced transition from the behavior caused by easy-plane anisotropy to the behavior caused by single-ion anisotropy. The revealed size-induced transition is accompanied by a spin-flop effect.

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Wang, Hanchen, Yuben Yang, Marco Madami, Yizhan Wang, Mian Du, Jilei Chen, Yu Zhang et al. « Anomalous anisotropic spin-wave propagation in thin manganite films with uniaxial magnetic anisotropy ». Applied Physics Letters 120, n^o 19 (9 mai 2022) : 192402. http://dx.doi.org/10.1063/5.0088546.

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Manipulation of the spin-wave coherent length is highly desirable to overcome intrinsic damping and to improve functionalities of magnonics materials and devices. In this work, based on angle-resolved propagating spin-wave spectroscopy and micro-focused Brillouin light scattering, we report a giant anisotropy of spin wave propagation in a 20 nm-thick La0.67Sr0.33MnO3 film grown on a NdGaO3 substrate. Vanishing of such anisotropic features in reference experiments where the La0.67Sr0.33MnO3 film is grown on SrTiO3 suggests that the anisotropic spin-wave propagation might be originated from different lattice mismatches of the LSMO film with these two substrates. Interestingly, the decay length and the relaxation time of spin waves are found to be largest when the wavevector is along the [110] crystalline orientation, which is neither at easy nor hard axis related to the in-plane uniaxial magnetic anisotropy. This suggests the possibility of individual control of the magnetic anisotropy and spin-wave anisotropy via strain engineering. Our discovery may enrich the material systems for anisotropic spin wave behavior and promote strain engineering and optimization of versatile magnonic devices.

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Мартынов, С. Н. « Основное состояние двухподрешеточного анизотропного ферромагнетика в магнитном поле ». Физика твердого тела 63, n^o 8 (2021) : 1090. http://dx.doi.org/10.21883/ftt.2021.08.51159.056.

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The ground state of a classical ferromagnet with the noncollinear single-ion anisotropy axes of the two sublattices and antisymmetric and anisotropic symmetric exchanges between the sublattices has been considered in a magnetic field applied in the hard magnetic directions of the crystal. The threshold conditions on the anisotropic interactions parameters determined the ground state among the three possible magnetic phases have been obtained. Depended on the type of the ground state and field direction the transition between the phases occurs as a phase transition first or second order. The value of the antisymmetric exchange above that the reorientation between two noncollinear phases is terminated by the second order phase transition depends on the angle between the local easy axes and the value of single-ion anisotropy. The field dependences of the magnetization and susceptibility have been calculated for the different ground states. The comparison with the results of the magnetic measurements in the highly anisotropic ferromagnet PbMnBO_4 has been made.

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Щербаков, С. В., А. Г. Налогин, В. Г. Костишин, А. С. Семенов, Н. Е. Адиатулина, А. А. Алексеев, Е. А. Белоконь, А. В. Тимофеев et Д. Н. Читанов. « Температурная зависимость эффективного поля магнитной анизотропии и ширины линии ферромагнитного резонанса поликристаллических сложнозамещенных гексагональных магнитноодноосных ферритов в диапазоне частот 25-67 GHz ». Журнал технической физики 90, n^o 5 (2020) : 782. http://dx.doi.org/10.21883/jtf.2020.05.49179.161-19.

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In the work in the frequency range 25 – 67 GHz the temperature changes of the effective magnetic anisotropy field and ferromagnetic resonance linewidth of the samples isotropic and anisotropic hexaferrite SrFe11.2Al0.1Si0.15Ca0.15O19 and anisotropic hexaferrite BaFe10.4Al1.4Si0.15Mn0.1O19 were studied. The samples obtained by ceramic technology with the pressing of the raw blanks in a magnetic field of 10 kOe. The studies were carried out in the temperature range+25 – +85 ºC. It was found that in the specified temperature range, the change in magnetic anisotropy is 9.8 Oe/ºC for barium hexaferrite and 4.2 Oe/ºC for strontium hexaferrite, and the change in ferromagnetic resonance linewidth is 12.2 Oe/ºC for barium hexaferrite and 10 – 12.3 Oe/ºC for strontium hexaferrite.

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Kiseleva, Tatiana Yu, Sergey I. Zholudev, Alla A. Novakova, Tatiana S. Gendler, Igor A. Il’inych, A. I. Smarzhevskaya, Yuriy Anufriev et Tatiana F. Grigorieva. « Magnetodeformational Anisotropy of FeGa/PU Hybrid Nanocomposite via Particle Concentration and Spatial Orientation ». Solid State Phenomena 233-234 (juillet 2015) : 607–10. http://dx.doi.org/10.4028/www.scientific.net/ssp.233-234.607.

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The present work has been undertaken to research effects of structure, morphology, volume fraction, spatial arrangement of magnetostrictive intermetallic FeGa alloy particles dispersed in modified polyurethane matrix. Correlation of composite magnetic behavior with structure and mechanical properties has been obtained by measurements of magnetostriction, remanent magnetization anisotropy, SEM, and dynamical mechanical analysis. Anisotropic chain structures of magnetic particles within the polymer with different interparticle interactions were observed. The increase of the magnetostrictive response with tailor-made magnetic anisotropy induced by magnetic particles volume fraction has been demonstrated

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Chen, Jianfeng, Yingli Liu et Qisheng Yin. « C-axis Oriented Polycrystalline BaFe12-xCoxO19 (x = 0, 0.3, 0.6, 0.9) for Millimeter Wave Self-biased Circulator at Ka Band ». Highlights in Science, Engineering and Technology 35 (11 avril 2023) : 40–45. http://dx.doi.org/10.54097/hset.v35i.7025.

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The anisotropic hexagonal magnetic material is prepared using conventional ceramic process. The high magnetic anisotropy field of hexagonal is essential to extend the device bandwidth for circulator operating at millimeter wave band. The modified hexagonal BaFe12-xCoxO19 with about 9 kOe anisotropy field and its Electromagnetic property are presented. And a simulation certificating the circulator at Ka-band is given at the end of the paper.

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ACHARYYA, MUKTISH. « AXIAL AND OFF-AXIAL DYNAMIC TRANSITIONS IN UNIAXIALLY ANISOTROPIC HEISENBERG FERROMAGNET : A COMPARISON ». International Journal of Modern Physics C 14, n^o 01 (janvier 2003) : 49–59. http://dx.doi.org/10.1142/s0129183103004206.

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Uniaxially anisotropic Heisenberg ferromagnet, in the presence of a magnetic field varying sinusoidally in time, is studied by Monte Carlo simulation. The axial (field applied only along the direction of anisotropy) and off-axial (field applied only along the direction which is perpendicular to the direction of anisotropy) dynamic transitions are studied. By studying the distribution of the dynamic order parameter component, it is observed that the axial transition is discontinuous for low anisotropy and becomes continuous in high anisotropy. The off-axial transition is found to be continuous for all values of anisotropy. In the infinite anisotropy limit, both types of transitions are compared with that observed in an Ising ferromagnet for the same value of the field and frequency. The infinitely anisotropic axial transition and dynamic transition in the Ising ferromagnet occur at different temperatures, whereas the infinitely anisotropic off-axial transition and the equilibrium ferro-para transition in the Ising model occur at the same temperature.

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Amoroso, Danila, Paolo Barone et Silvia Picozzi. « Interplay between Single-Ion and Two-Ion Anisotropies in Frustrated 2D Semiconductors and Tuning of Magnetic Structures Topology ». Nanomaterials 11, n^o 8 (21 juillet 2021) : 1873. http://dx.doi.org/10.3390/nano11081873.

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The effects of competing magnetic interactions in stabilizing different spin configurations are drawing renewed attention in order to unveil emerging topological spin textures and to highlight microscopic mechanisms leading to their stabilization. The possible key role of the two-site exchange anisotropy in selecting specific helicity and vorticity of skyrmionic lattices has only recently been proposed. In this work, we explore the phase diagram of a frustrated localized magnet characterized by a two-dimensional centrosymmetric triangular lattice, focusing on the interplay between the two-ion anisotropy and the single-ion anisotropy. The effects of an external magnetic field applied perpendicularly to the magnetic layer, are also investigated. By means of Monte Carlo simulations, we find an abundance of different spin configurations, going from trivial to high-order Q skyrmionic and meronic lattices. In closer detail, we find that a dominant role is played by the two-ion over the single-ion anisotropy in determining the planar spin texture; the strength and the sign of single ion anisotropy, together with the magnitude of the magnetic field, tune the perpendicular spin components, mostly affecting the polarity (and, in turn, the topology) of the spin texture. Our analysis confirms the crucial role of the anisotropic symmetric exchange in systems with dominant short-range interactions; at the same time, we predict a rich variety of complex magnetic textures, which may arise from a fine tuning of competing anisotropic mechanisms.

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Wu, Honghong, Shiyong Huang, Xin Wang, Liping Yang et Zhigang Yuan. « Influence of Intermittency on the Energy Transfer Rate of Solar Wind Turbulence ». Astrophysical Journal Letters 958, n^o 2 (27 novembre 2023) : L28. http://dx.doi.org/10.3847/2041-8213/ad0a68.

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Abstract The intermittency in the solar wind turbulence manifests itself in the anisotropic scaling due to the anisotropic spectral index and the intermittent level based on the extended P model. However, the influence of intermittency on the energy transfer rate remains unclear. Here we apply the partial variance of increments method to identify the intermittency for the magnetic field measurements in the fast solar wind from the Ulysses spacecraft. We distinguish the sampling direction using the angle θ RB between the local magnetic field and radial direction to study the anisotropy. We perform the multiorder structure function analyses and adopt the log-Poisson cascade model to describe the role of intermittency in the cascade process. We find that the anisotropy of the scaling becomes isotropic with a complete removal of intermittency. We compare explicitly the anisotropy of the energy transfer rate before and after removing the intermittency for the same interval for the first time. We find a distinct anisotropy with a cascade enhancement in the direction perpendicular to the local magnetic field. The removal of the intermittency greatly weakens the anisotropy by mainly reducing the perpendicular energy transfer rate. Our findings suggest that the intermittency effectively enhances the energy transfer rate, in particular in the perpendicular direction in the solar wind turbulence.

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Szumiata, Tadeusz, Paweł Rekas, Małgorzata Gzik-Szumiata, Michał Nowicki et Roman Szewczyk. « The Two-Domain Model Utilizing the Effective Pinning Energy for Modeling the Strain-Dependent Magnetic Permeability in Anisotropic Grain-Oriented Electrical Steels ». Materials 17, n^o 2 (11 janvier 2024) : 369. http://dx.doi.org/10.3390/ma17020369.

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This paper presents a newly proposed domain wall energy-based model of the 2D strain dependence of relative magnetic permeability in highly grain-oriented anisotropic electrical steels. The model was verified utilizing grain-oriented M120-27s electrical steel sheet samples with magnetic characteristics measured by an automated experimental setup with a magnetic yoke. The model’s parameters, identified in the differential evolution-based optimization process, enable a better understanding of the interaction between stress-induced anisotropy and magnetocrystalline anisotropy in electrical steels. Moreover, the consequences of the simplified description of grain-oriented magnetocrystalline anisotropy are clearly visible, which opens up the possibility for further research to improve this description.

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Liang, Wenhui, Fengxia Hu, Jian Zhang, Hao Kuang, Jia Li, Jiefu Xiong, Kaiming Qiao, Jing Wang, Jirong Sun et Baogen Shen. « Anisotropic nonvolatile magnetization controlled by electric field in amorphous SmCo thin films grown on (011)-cut PMN-PT substrates ». Nanoscale 11, n^o 1 (2019) : 246–57. http://dx.doi.org/10.1039/c8nr06449k.

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Ubizskii, S. B., L. P. Pavlyk et I. I. Syvorotka. « Ferromodulation Effect Usage for the Magnetic Film Anisotropy Investigation ». Solid State Phenomena 190 (juin 2012) : 234–37. http://dx.doi.org/10.4028/www.scientific.net/ssp.190.234.

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The ferromodulation effect response model of an anisotropic soft magnetic film placed in the crossed permanent bias and alternating excitation magnetic fields is built. It was shown theoretically and experimentally how such a field configuration can be used for registering the effects relating to the film magnetic anisotropy properties.

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Bouknia, Mohamed Lamine, Chemseddine Zebiri, Djamel Sayad, Issa Elfergani, Jonathan Rodriguez, Mohammad Alibakhshikenari, Raed A. Abd-Alhameed, Francisco Falcone et Ernesto Limiti. « Theoretical Study of the Input Impedance and Electromagnetic Field Distribution of a Dipole Antenna Printed on an Electrical/Magnetic Uniaxial Anisotropic Substrate ». Electronics 10, n^o 9 (29 avril 2021) : 1050. http://dx.doi.org/10.3390/electronics10091050.

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The present work considers the investigation of the effects of both electrical and magnetic uniaxial anisotropies on the input impedance, resonant length, and fields distribution of a dipole printed on an anisotropic grounded substrate. In this study, the associated integral equation, based on the derivation of the Green’s functions in the spectral domain, is numerically solved employing the method of moments. In order to validate the computing method and the evaluated calculation code, numerical results are compared with available data in the literature treating particular cases of electrical uniaxial anisotropy; reasonable agreements are reported. Novel results of the magnetic uniaxial anisotropy effects on the input impedance and the evaluated electromagnetic field are presented and discussed. This work will serve as a stepping stone for further works for a better understanding of the electromagnetic field behavior in complex anisotropic and bi-anisotropic media.

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Гохфельд, Д. М., et Д. А. Балаев. « Анизотропия намагниченности текстурированного ВТСП Bi-2223 в сильных магнитных полях ». Физика твердого тела 62, n^o 7 (2020) : 1017. http://dx.doi.org/10.21883/ftt.2020.07.49465.031.

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We elucidate reasons of low values of the magnetization anisotropy for bulk textured samples consisting of strong anisotropic crystallites of (Bi,Pb)2Sr2Ca2Cu3Ox (Bi-2223) superconductor. It was found that the observed anisotropy was linked with the disordered arrangement of Bi-2223 crystallites in the sample. The magnetic angle, which is a characteristic of the disorder, can be determined by measuring the anisotropy of textured superconductors.

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Ben, Tong, Yuqi Kong, Long Chen, Fangyuan Chen et Xian Zhang. « Magnetostriction property modeling of silicon steel considering stress-induced and magnetocrystalline anisotropy ». AIP Advances 13, n^o 2 (1 février 2023) : 025031. http://dx.doi.org/10.1063/9.0000421.

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This paper proposed an improved magnetostriction model for correlation of anisotropy in non-oriented (NO) silicon steel based on the free energy, which considers stress-induced and magnetocrystalline anisotropy. Firstly, the free energy model, which includes stress-induced anisotropy energy, the energy of magnetic field, and the anisotropic energy of magnetic crystals, is incorporated into the anhysteretic magnetization parameter M an. Then, to obtain the magnetic field and proposed model parameters related to stress-induced and magnetocrystalline anisotropy, the magnetostrictive strain loops at different magnetization directions of NO silicon steel are measured. Finally, based on the parameters obtained from experimental data of the proposed model, magnetostrictive strain loops under varying magnetization directions are simulated. This improved magnetostriction model can be applied to the calculation of the vector magnetostriction of the motor core.

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Upadhaya, Brijesh, Floran Martin, Paavo Rasilo, Paul Handgruber, Anouar Belahcen et Antero Arkkio. « Modelling anisotropy in non-oriented electrical steel sheet using vector Jiles–Atherton model ». COMPEL - The international journal for computation and mathematics in electrical and electronic engineering 36, n^o 3 (2 mai 2017) : 764–73. http://dx.doi.org/10.1108/compel-09-2016-0399.

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Purpose Non-oriented electrical steel presents anisotropic behaviour. Modelling such anisotropic behaviour has become a necessity for accurate design of electrical machines. The main aim of this study is to model the magnetic anisotropy in the non-oriented electrical steel sheet of grade M400-50A using a phenomenological hysteresis model. Design/methodology/approach The well-known phenomenological vector Jiles–Atherton hysteresis model is modified to correctly model the typical anisotropic behaviour of the non-oriented electrical steel sheet, which is not described correctly by the original vector Jiles–Atherton model. The modification to the vector model is implemented through the anhysteretic magnetization. Instead of the commonly used classical Langevin function, the authors introduced 2D bi-cubic spline to represent the anhysteretic magnetization for modelling the magnetic anisotropy. Findings The proposed model is found to yield good agreement with the measurement data. Comparisons are done between the original vector model and the proposed model. Another comparison is also made between the results obtained considering two different modifications to the anhysteretic magnetization. Originality/value The paper presents an original method to model the anhysteretic magnetization based on projections of the anhysteretic magnetization in the principal axis, and apply such modification to the vector Jiles–Atherton model to account for the magnetic anisotropy. The replacement of the classical Langevin function with the spline resulted in better fitting. The proposed model could be used in the numerical analysis of magnetic field in an electrical application.

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Pogorily, A. M., D. M. Polishchuk, A. I. Tovstolytkin, A. F. Kravets, V. O. Zamorskyi, A. V. Nosenko et V. K. Nosenko. « Resonance Properties and Magnetic Anisotropy of Nanocrystalline Fe73Cu1Nb3Si16B7 Alloy ». Ukrainian Journal of Physics 64, n^o 10 (1 novembre 2019) : 942. http://dx.doi.org/10.15407/ujpe64.10.942.

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Resonance properties of nanocrystalline ribbons of Fe73Cu1Nb3Si16B7 alloy annealed with the use of an electric current under a tensile stress of 180 MPa have been studied within the ferromagnetic resonance method. Two kinds of ferromagnetic regions with different anisotropic behaviors that coexist in the alloy after the annealing are detected. One of them is amorphous and weakly magnetically anisotropic, whereas the other is characterized by a pronounced uniaxial magnetic anisotropy and corresponds to the nanocrystalline phase. Quantitative estimations of magnetic parameters in two magnetic phases of the alloy are made.

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Aneli, Jimsher, Levan Nadareishvili, Grigor Mamniashvili, Anatoli Akhalkatsi et Gennady Zaikov. « Gradiently Anisotropic Conducting and Magnetic Polymer Composites ». Chemistry & ; Chemical Technology 6, n^o 3 (20 septembre 2012) : 285–89. http://dx.doi.org/10.23939/chcht06.03.285.

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Ghorbanalilu, Mohammad, et Elahe Abdollahazadeh. « Extension of temperature anisotropy Weibel instability to non-Maxwellian plasmas by 2D PIC simulation ». Laser and Particle Beams 36, n^o 1 (29 décembre 2017) : 1–7. http://dx.doi.org/10.1017/s0263034617000842.

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AbstractThe Weibel instability driven by temperature anisotropy is investigated in a two-dimensional (2D) particle-in-cell simulation in non-extensive statistics in the relativistic regime. In order to begin the simulation, we introduced a new 2D anisotropic distribution function in the context of non-extensive statistics. The heavy ions considered to be immobile and form the neutralizing background. The numerical results show that non-extensive parameterqplays an important role on the magnetic field saturation time, the time of reduction temperature anisotropy, evolution time to the quasi-stationary state, and the peak energy density of magnetic field. We observe that the instability saturation time increases by increasing the non-extensive parameterq. It is shown that structures with superthermal electrons (q< 1) could generate strong magnetic fields during plasma thermalization. The simulation results agree with the previous simulations for an anisotropic Maxwellian plasma (q= 1).

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Nowicki, Michał, Roman Szewczyk et Paweł Nowak. « Experimental Verification of Isotropic and Anisotropic Anhysteretic Magnetization Models ». Materials 12, n^o 9 (11 mai 2019) : 1549. http://dx.doi.org/10.3390/ma12091549.

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The anhysteretic magnetization curve is the key element of modeling magnetic hysteresis loops. Despite the fact that it is intensively exploited, known models of anhysteretic curve have not been verified experimentally. This paper presents the validation of four anhysteretic curve models considering four different materials, including isotropic, such as Mn-Zn soft ferrite, as well as anisotropic amorphous and nanocrystalline alloys. The presented results indicate that only the model that considers anisotropic energy is valid for a wide set of modern magnetic materials. The most suitable of the verified models is the anisotropic extension function-based model, which considers uniaxial anisotropy.

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Balaji, C., S. Maruthamanikandan, C. Rudresha et V. Vidya Shree. « Anisotropic Darcy–Brinkman Magnetic Fluid Convection under the Influence of a Time-Dependent Sinusoidal Magnetic Field ». Ukrainian Journal of Physics 68, n^o 11 (18 décembre 2023) : 730. http://dx.doi.org/10.15407/ujpe68.11.730.

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The impact of the sinusoidal mode of a magnetic field involving time fluctuations on the threshold of the ferromagnetic smart liquid convection in a saturated permeable medium is investigated using the regular perturbation technique. The Darcy–Brinkman model with anisotropic permeability is used to describe the flow through porous media. The thermal anisotropy is implemented in the energy equation. The problem might be useful in thermal engineering applications such as dynamic loudspeakers and computer hard discs and in medical applications like the treatment of tumor cells and the cell separation, to name a few. The regular perturbation technique is based on the minimum amplitude of a magnetic field modulation, and the onset criterion is dealt with in terms of a correction in the critical Rayleigh number and wavenumber. The thermal Rayleigh number correction depends on the magnetic field modulation frequency, magnetic force, anisotropies, porosity, and Prandtl number. At moderate values of the magnetic field modulation frequency, the impact of various physical factors is perceived to be noteworthy. The influences of the magnetic mechanism, Prandtl number, porosity parameter, and Brinkman number are shown to augment the destabilizing effect of the magnetic field modulation for moderate values of the frequency of a modulation. However, the destabilizing effect of the magnetic field modulation is diminished due to an increase in the values of the mechanical anisotropy parameter and thermal anisotropy parameter. The study reveals that the effect of the magnetic field modulation could be exploited to control the convective instability in an anisotropic porous medium saturated by a ferromagnetic fluid.

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Elhag, S. H., et F. S. Bayones. « Effect of Rotation, Gravity, Primary Stress and Magnetic Field on Shear Waves Spreading in an Anisotropic Incompressible Sandy Elastic Medium ». Journal of Computational and Theoretical Nanoscience 16, n^o 11 (1 novembre 2019) : 4443–54. http://dx.doi.org/10.1166/jctn.2019.8610.

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In this paper, we investigated the spreading of shear wave in an anisotropic non-homogeneous elastic medium under effect of dry sand, rotation, gravity, primary stress, and magnetic field. We have reached equation of variation of shear wave velocity c1 in an anisotropic incompressible medium according to sand, rotation, gravity, primary stress, and magnetic field, then we used graphs to illustrate to show the effect of direction of spreading of shear wave. The results indicate that the effect of dry sand, rotation, gravity, primary stress, and magnetic field on the spreading of shear wave in an anisotropic inhomogeneous elastic medium are very pronounced. The results have been obtained are discussed and presented visually, the results demonstrate that the effect of sand, gravity field, primary stress, magnetic field, anisotropy and rotation are noticeable.

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BOTTAUSCIO, ORIANO, VALERIA CHIADÒ PIAT, MICHELA ELEUTERI, LUCA LUSSARDI et ALESSANDRA MANZIN. « DETERMINATION OF THE EQUIVALENT ANISOTROPY PROPERTIES OF POLYCRYSTALLINE MAGNETIC MATERIALS : THEORETICAL ASPECTS AND NUMERICAL ANALYSIS ». Mathematical Models and Methods in Applied Sciences 23, n^o 07 (2 avril 2013) : 1217–33. http://dx.doi.org/10.1142/s0218202513500073.

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The aim of this paper is the determination of the equivalent anisotropy properties of polycrystalline magnetic materials, modeled as an assembly of monocrystalline grains with a stochastic spatial distribution of easy axes. The theory of Γ-convergence is here adopted to homogenize the anisotropic contribution in the energy functional and derive the equivalent anisotropy properties. The reliability of this approach is investigated focusing on the computation of the static hysteresis loops of polycrystalline magnetic thin films, starting from the numerical integration of the Landau–Lifshitz–Gilbert equation.

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WANG, ZHAO-MING, et YUAN CHEN. « DOUBLE-TIME GREEN'S FUNCTION APPROACH TO THE SPIN 1/2 SPATIALLY ANISOTROPIC ANTIFERROMAGNETIC HEISENBERG MODEL ». International Journal of Modern Physics B 18, n^o 25 (20 octobre 2004) : 3361–71. http://dx.doi.org/10.1142/s0217979204026500.

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By use of the double-time Green's function method in the cubic-lattice S=1/2 anisotropic antiferromagnetic two-sublattice Heisenberg model, in the Tyablikov approximation, the staggered magnetization m, the correlation function and the static susceptibility are investigated. And the effects of spatial anisotropy are explored. The magnetic properties of this model are found to be dependent of anisotropy.

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Alkherayf, Fahad A., Eve C. Tsai, Thanh Nguyen, Garth Johnson et Arturo Cardenas-Blanco. « Fractional Anisotrophy and Tractography : A Novel Technique To Improve Clinical Correlation of Motor Deficits With Spinal Cord Magnetic Resonance Imaging in Patients With Spinal Cord Injury ». Neurosurgery 67, n^o 2 (1 août 2010) : 546–47. http://dx.doi.org/10.1227/01.neu.0000387004.27497.1b.

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Wang, Chun, Sanmin Ke et Zhen Wang. « Magnetic Properties Regulation of FeGa and FeGaNi Films with Oblique Magnetron Sputtering ». Magnetochemistry 8, n^o 10 (20 septembre 2022) : 111. http://dx.doi.org/10.3390/magnetochemistry8100111.

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Magnetic FeGa and FeGaNi films with an in-plane anisotropy were deposited by employing oblique magnetron sputtering. With the increase in oblique angle, the crystallite size of FeGa decreases, which indicates that oblique sputtering can refine the crystallite size. The remanence ratio of FeGa films increases from 0.5 to 0.92 for an easy axis, and the coercivity increases with the decrease in the crystallite size. The calculated static anisotropic field shows that the in-plane magnetic anisotropy can be induced by oblique sputtering and the strength increases with the oblique sputtering angle. After doping Ni by co-sputtering, FeGaNi films exhibit a stable remanence ratio at 0.8, low coercivity and good anisotropy. With the low sputtering power of the Ni target, there is a competitive relationship between the effect of crystallite size and Ni doping which causes the coercivity of FeGaNi films to first increase and then decrease with the increase in the oblique angle. The FeGaNi film also shows high anisotropy in a small oblique angle. The variation of coercivity and anisotropy of FeGaNi films can be explained by the crystalline size effect and increase in Ni content. For the increasing intensity of collisions between FeGa and Ni atoms in the co-sputtering, the in-plane magnetic anisotropy increases first and then decreases. As a result, the magnetic properties of FeGa films were examined to tailor their magnetic softness and magnetic anisotropy by controlling the oblique sputtering angle and Ni doping.

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Blunk, Inken. « Magnetic Susceptibility Anisotropy and Deformation in Quaternary Lake Sediments ». Zeitschrift der Deutschen Geologischen Gesellschaft 140, n^o 2 (1 janvier 1989) : 393–403. http://dx.doi.org/10.1127/zdgg/140/1989/393.

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Kotadia, Irum, John Whitaker, Caroline Roney, Steven Niederer, Mark O’Neill, Martin Bishop et Matthew Wright. « Anisotropic Cardiac Conduction ». Arrhythmia & ; Electrophysiology Review 9, n^o 4 (24 décembre 2020) : 202–10. http://dx.doi.org/10.15420/aer.2020.04.

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Anisotropy is the property of directional dependence. In cardiac tissue, conduction velocity is anisotropic and its orientation is determined by myocyte direction. Cell shape and size, excitability, myocardial fibrosis, gap junction distribution and function are all considered to contribute to anisotropic conduction. In disease states, anisotropic conduction may be enhanced, and is implicated, in the genesis of pathological arrhythmias. The principal mechanism responsible for enhanced anisotropy in disease remains uncertain. Possible contributors include changes in cellular excitability, changes in gap junction distribution or function and cellular uncoupling through interstitial fibrosis. It has recently been demonstrated that myocyte orientation may be identified using diffusion tensor magnetic resonance imaging in explanted hearts, and multisite pacing protocols have been proposed to estimate myocyte orientation and anisotropic conduction in vivo. These tools have the potential to contribute to the understanding of the role of myocyte disarray and anisotropic conduction in arrhythmic states.

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KRZYSZTON, T. « SURFACE BARRIER IN THE MIXED STATE OF ANISOTROPIC SUPERCONDUCTOR ». Modern Physics Letters B 07, n^o 12 (20 mai 1993) : 841–47. http://dx.doi.org/10.1142/s0217984993000837.

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In the framework of London theory, the problem of equilibrium between magnetic flux density in the anisotropic superconductor and the applied external magnetic field is studied. The Gibbs free energy of a fluxoid in the presence of magnetic flux density in the sample is calculated. As a result, critical entry and exit fields are calculated and their dependence upon the angle which makes anisotropy axis and the direction of an external magnetic field.

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Treumann, R. A., et W. Baumjohann. « Brief Communication : Weibel, Firehose and Mirror mode relations ». Nonlinear Processes in Geophysics 21, n^o 1 (22 janvier 2014) : 143–48. http://dx.doi.org/10.5194/npg-21-143-2014.

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Abstract. Excitation of Weibel magnetic fields in an initially non-magnetized though anisotropic plasma may trigger other low-frequency instabilities fed by pressure anisotropy. It is shown that under Weibel-like stable conditions the Weibel-like thermal fluctuation magnetic field allows for restricted Firehose-mode growth. In addition, low-frequency Whistlers can also propagate in the plasma under certain anisotropic conditions. When the Weibel-like mode becomes unstable, Firehose instability ceases but Mirror modes take over. This will cause bubble structures in the Weibel-like field in addition to filamentation.

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Halauchuk V. I., Bumai Y. A., Lukashevich M. G., Lyadov N. M., Faizrakhmanov I. A. et Khaibullin R.I. « Correlation between electrical, galvanomagnetic and magnetic properties of nanocrystalline iron films obtained by ion assisted deposition ». Physics of the Solid State 64, n^o 14 (2022) : 2366. http://dx.doi.org/10.21883/pss.2022.14.54335.163.

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Here we present the measurements of the temperature dependence of resistance, transverse and longitudinal magnetoresistance (MR) in nanocrystalline iron films in the temperature range 2-300 K and the sweep of the magnetic field up to 8 T. Thin nanocrystalline films of α-iron phase with 80 nm thickness were obtained by ion-beam assisted deposition on a silicon substrate. In addition to the shape anisotropy, the obtained iron films exhibited perpendicular magnetic anisotropy (PMA), which disappeared after annealing the films at a temperature of 450oC in a vacuum. The effect of PMA on the sign and magnitude of the MR of iron films, as well as on the magnetic field dependences of the magnetoresistive effect, recorded at different orientations of the external magnetic field with respect to the film plane and current direction, is experimentally shown. The results obtained are discussed in the framework of modern views on the processes of charge transfer in a weakly disordered ferromagnetic films with different magnetic anisotropy and domain structure when a weak (less than the saturation field of magnetization) or strong (higher than the saturation field) external magnetic field is applied. Keywords: nanocrystalline iron films, perpendicular magnetic anisotropy, magnetoresistance, anisotropic magnetoresistance, magnon magnetoresistance, percolation, weak localization.

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Sabirianov, R. « Magnetic anisotropy and anisotropic ballistic conductance of thin magnetic wires ». Journal of Magnetism and Magnetic Materials 300, n^o 1 (mai 2006) : 136–39. http://dx.doi.org/10.1016/j.jmmm.2005.10.050.

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BÎRSAN, EUGEN, et OLIVIAN NIGA. « MONTE CARLO APPROACH ON DOUBLE-LAYER MAGNETIC SPIN LATTICE IN ANISOTROPIC HEISENBERG MODEL ». International Journal of Modern Physics B 23, n^o 02 (20 janvier 2009) : 251–64. http://dx.doi.org/10.1142/s021797920904967x.

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In this paper, we investigate the magnetic properties of double-layer thin film using Monte Carlo technique, in anisotropic Heisenberg model. The magnetization, out-of-plane and in-plane magnetic susceptibilities, and also the specific heat behaviors according to temperature are investigated in order to find out the contingent magnetic ordering phases and the critical temperatures values, for two easy-axis anisotropy parameters settings. We also calculate the relative variation rate of the critical temperature along with the easy-plane anisotropy interaction parameter distribution, and we comparatively appraise the numerical obtained results, in order to get quantitative response on the physical model parameters changes. Finally, we present a finite size effect study on magnetic susceptibility, respecting the two settings physical parameters we assumed in the paper.

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Kijima-Aoki, Hanae, Yasushi Endo, Takamichi Miyazaki, Tsutomu Nojima, Kenji Ikeda, Nobukiyo Kobayashi, Shigehiro Ohnuma et Hiroshi Masumoto. « Shape effect of Co nanoparticles on the electric and magnetic properties of Co–SiO₂ nanogranular films ». AIP Advances 12, n^o 3 (1 mars 2022) : 035229. http://dx.doi.org/10.1063/9.0000310.

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Controlling the magnetic anisotropy of nanoparticles is a crucial but challenging step for developing new magnetic functions. Here, we demonstrate a simple approach to controlling the shape of Co nanoparticles in a Co-SiO2 nanogranular film from oblate to prolate spheroid by varying the substrate rotation speed during the tandem fabrication process without changing the film composition (Co:SiO2 = 3:7). Changing the nanoparticles from oblate to prolate, increasing perpendicular length of ellipsoidal nanoparticles, changes the magnetic anisotropy axis of Co–SiO2 nanogranular films from in-plane to out-of-plane, which indicates that the shape anisotropy profoundly affects the magnetic properties. Despite the small tunneling current of a few tens of nanoamperes, a maximum tunneling magnetoresistance effect of up to 2.8 % was realized under an applied magnetic field of 12 kOe in the film plane. Achieving both in-plane and perpendicular spin-dependent tunneling, the anisotropic nanogranular films imply direction controllable tunneling materials as future topological nanoarchitecture. Such high-resistivity nanogranular films with a controllable magnetic nanoparticle shape facilitate the design of new magneto-optical devices with high withstand voltages.

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SU, C. W., S. C. CHANG et Y. C. CHANG. « MAGNETO-OPTIC FARADAY EFFECT ON SPIN ANISOTROPIC Co ULTRATHIN FILMS AND POST-NITRIDIZATION ON ZnO(002) CRYSTAL ». SPIN 02, n^o 04 (décembre 2012) : 1250017. http://dx.doi.org/10.1142/s2010324712500178.

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Perpendicular magnetic anisotropy in the initial growth of epitaxial in-plane anisotropic Co ultrathin films on the ZnO (002) crystal surface was discovered. The critical thickness of weak spin reorientation transition phenomenon in deposition process from in-plane to out-of-plane magnetic anisotropy is around 2 nm. Ultrathin 1.2 nm Co film was stabilized by post-irradiation of low-energy N ions from the observation of hysteresis loop transforming from an S-shape soft magnetic state to a square hard magnetic state. The addition of N affected the magnetic behavior. The time-dependent nitridization process was observed using Auger electron spectroscopy. Magneto-optical Faraday effect measurements were used to observe the magnetic properties of high-transmission Co/ZnO (002) and Co–N/ZnO (002) surface. A strong polar magneto-optic Faraday effect was dominated in the 2.0–4.0 nm Co/ZnO (002) surfaces. From the N+ implantation that reduces the corresponding coercivity, a hexagonal c-axis lattice structure of Co with a preferred perpendicular anisotropy on the ZnO (002) surface may be explained.

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Yuan, Ning, Xiao Chun Nie, Richard Liu et Cheng Wei Qiu. « Simulation of full responses of a triaxial induction tool in a homogeneous biaxial anisotropic formation ». GEOPHYSICS 75, n^o 2 (mars 2010) : E101—E114. http://dx.doi.org/10.1190/1.3336959.

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Triaxial induction tools are used to evaluate fractured and low-resistivity reservoirs composed of thinly laminated sand-shale sequences. Thinly laminated and fractured reservoirs demonstrate transversely isotropic or fully anisotropic (biaxial anisotropic) electrical properties. Compared to the number of studies on transverse isotropy, relatively little work covers biaxial anisotropy because of the mathematical complexity. We have developed a theoretical analysis for the full response of a triaxial induction tool in a homogeneous biaxial anisotropic formation. The triaxial tool is composed of three mutually orthogonal transmitters and three mutually orthogonal receivers. The bucking coils are also oriented at three mutually orthogonal directions to remove direct coupling. Starting from the space-domain Maxwell’s equations, which the electromagnetic (EM) fields satisfied, we obtain the spectral-domain Maxwell’s equations by defining a Fourier transform pair. Solving the resultant spectral-domain vector equation, we can find the spectral-domain solution for the electric field. Then, the magnetic fields can be determined from a homogeneous form of Maxwell’s equations. The solution for the EM fields in the space domain can be expressed in terms of inverse Fourier transforms of their spectral-domain counterparts. We use modified Gauss-Laguerre quadrature and contour integration methods to evaluate the inverse Fourier transform efficiently. Our formulations are based on arbitrary relative dipping and azimuthal and tool angles; thus, we obtain the full coupling matrix connecting source excitations to magnetic field response. We have validated our formulas and investigated the effects of logging responses on factors such as relative dipping, azimuthal and tool angles, and frequency using our code. We only consider conductivity anisotropy, not anisotropy in dielectric permittivity and magnetic permeability. However, our method and formulas are straightforward enough to consider anisotropy in dielectric permittivity.

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Bartolomé, Juan, E. Bartolomé, V. V. Eremenko, V. V. Ibulaev, Valentyna Sirenko et Yu T. Petrusenko. « Magnetic Anisotropy in 2H-NbSe₂ Electron Irradiated Single Crystals ». Solid State Phenomena 152-153 (avril 2009) : 470–73. http://dx.doi.org/10.4028/www.scientific.net/ssp.152-153.470.

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The anisotropic magnetic properties of the metallic layered compound with hexagonal crystal structure 2H-NbSe2 are investigated as a function of their dependence on high-energy electron irradiation. Pauli paramagnetism of free electrons is shown to dominate the magnetic susceptibility, P. The anisotropy is related to spin-orbit effects on the hybridized electronic states. Irradiation affects the density of states at the Fermi surface, increasing both P and the anisotropy. Below a threshold temperature, TS=54 K, the paramagnetic contribution, which increases with the dose, is ascribed to dangling bonds, nanotubes and nanorods generated by irradiation.

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HARKO, T., et M. K. MAK. « BIANCHI TYPE I UNIVERSES WITH DILATON AND MAGNETIC FIELDS ». International Journal of Modern Physics D 11, n^o 08 (septembre 2002) : 1171–82. http://dx.doi.org/10.1142/s0218271802002141.

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We consider the dynamics of a Bianchi type I spacetime in the presence of dilaton and magnetic fields. The general solution of the Einstein–Maxwell dilaton field equations can be obtained in an exact parametric form. Depending on the numerical values of the parameters of the model there are three distinct classes of solutions. The time evolution of the mean anisotropy, shear and deceleration parameters is considered in detail and it is shown that a magnetic-dilaton anisotropic Bianchi type I geometry does not isotropize, the initial anisotropy being present in the universe for all times.

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CABRERA, G. G., S. WEINKETZ et DJALMA MEDEIROS. « FINITE-SIZE CALCULATION OF ANISOTROPIC ANTIFERROMAGNETIC CHAINS AT NONZERO FIELD ». International Journal of Modern Physics B 10, n^o 12 (30 mai 1996) : 1453–68. http://dx.doi.org/10.1142/s0217979296000568.

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The antiferromagnetic spin-1/2 Heisenberg model, with axial anisotropy and applied magnetic field parallel to the axis, is solved numerically by Lanczos diagonalization of finite systems. We devise an extremely accurate method that allows for a reliable extrapolation to the infinite size limit. In the above limit, our results are compared with exact analytical solutions obtained through the Bethe ansatz. As an important example, we probe the behavior of the Critical Magnetic Field in the whole anisotropic region. We find indications that suggest the presence of two different regimes for the scaling of size effects as a function of the anisotropy.

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Stadler, Daniel, Thomas Brede, Danny Schwarzbach, Fernando Maccari, Thomas Fischer, Oliver Gutfleisch, Cynthia A. Volkert et Sanjay Mathur. « Anisotropy control in magnetic nanostructures through field-assisted chemical vapor deposition ». Nanoscale Advances 1, n^o 11 (2019) : 4290–95. http://dx.doi.org/10.1039/c9na00467j.

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CVD of Fe(CO)₅ in an external magnetic field (B = 1.00 T) was found to significantly affect the microstructure and anisotropy of as-deposited iron crystallites that could be transformed into anisotropic hematite nanorods by aerobic oxidation.

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Pashko, Anna G., R. G. Bareev, V. Osadchenko, N. Lobasheva et G. S. Kandaurova. « Dynamic Chains of Spiral Magnetic Domains ». Solid State Phenomena 168-169 (décembre 2010) : 227–29. http://dx.doi.org/10.4028/www.scientific.net/ssp.168-169.227.

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In this paper we present the results of investigation of spiral dynamic domains of a highly anisotropic iron garnet film with a perpendicular anisotropy in magnetic field with a constant dimensional gradient. The experiment showed how the presence of gradient of constant field affects the main parameters of spiral dynamic domains – geometrical form, life time, amount of orbits.

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Khaydukov, Yu N., Nikolai S. Perov, M. M. Borisov, E. Kh Mukhamedzhanov, A. Csik, K. N. Zhernenkov, Yu V. Nikitenko et V. L. Aksenov. « Structural and Magnetic Properties of the Periodic [Fe(5nm)/V(5nm)]₁₀ and [Fe (3nm)/V(3nm)]₂₀ Systems ». Solid State Phenomena 190 (juin 2012) : 396–400. http://dx.doi.org/10.4028/www.scientific.net/ssp.190.396.

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Results of the study of the structural and magnetic properties of periodic Fe/V heterostructures with periods D = 9.4nm and D = 6.3nm are present. The study has shown that ferromagnetic islands are formed on the interfaces of Fe and V. These islands have different magnetic properties as sub-layers of pure iron. Islands in the sample with the period D = 9.4 nm have anisotropic shape, which leads to the anisotropy of magnetic properties.

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