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Related papers: Thermal activation in permanent magnets

200 papers

Multiscale simulation is a key research tool for the quest for new permanent magnets. Starting with first principles methods, a sequence of simulation methods can be applied to calculate the maximum possible coercive field and expected…

Numerical integration of a stochastic Landau-Lifshitz-Gilbert equation is used to study dynamic processes in single-domain nanoscale magnets at nonzero temperatures. Special attention is given to including thermal fluctuations as a Langevin…

Materials Science · Physics 2009-10-31 Gregory Brown , M. A. Novotny , Per Arne Rikvold

Thermodynamic properties of cubic Heisenberg ferromagnets with competing exchange interactions are considered near the frustration point where the coefficient $D$ in the spin-wave spectrum $E_{\mathbf{k}}\sim D k^{2}$ vanishes. Within the…

Strongly Correlated Electrons · Physics 2015-04-21 A. N. Ignatenko , A. A. Katanin , V. Yu. Irkhin

Finite-temperature micromagnetics simulations are employed to study the magnetization-switching dynamics driven by a field applied at an angle to the long axis of an iron nanopillar. A bi-modal distribution in the switching times is…

Statistical Mechanics · Physics 2015-05-13 S. H. Thompson , G. Brown , P. A. Rikvold , M. A. Novotny

The effect of thermal fluctuations on a thin film magnetoresistive element has been calculated. The technique involves adding to the basic spin dynamics a general form of interaction with a thermal bath. For a general anisotropic magnetic…

Materials Science · Physics 2007-05-23 Vladimir L. Safonov , H. Neal Bertram

Features of thermally-activated magnetization switching have been studied in a FeCoB nanomagnet using the N\'eel model. A method of a high-precision measurement of the coercive field, retention time, {\Delta} and the size of the switching…

Mesoscale and Nanoscale Physics · Physics 2020-02-05 Vadym Zayets

In order to study the dependence of the coercive force of sintered magnets on temperature, nucleation and domain wall propagation at the grain boundary are studied as rate-determining processes of the magnetization reversal phenomena in…

Materials Science · Physics 2021-06-30 Sasmita Mohakud , Sergio Andraus , Masamichi Nishino , Akimasa Sakuma , Seiji Miyashita

Temperature dependence of the magnetocrystalline anisotropy energy and magnetization of the prototypical rare-earth magnet YCo$_5$ is calculated from first principles, utilizing the relativistic disordered local moment approach. We discuss…

Materials Science · Physics 2014-09-17 Munehisa Matsumoto , Rudra Banerjee , Julie B. Staunton

Magnetization reversal in permanent magnets occurs by the nucleation and expansion of reversed domains. Micromagnetic theory offers the possibility to localize the spots within the complex structure of the magnet where magnetization…

Materials Science · Physics 2018-05-25 J. Fischbacher , A. Kovacs , L. Exl J. Kühnel , E. Mehofer , H. Sepehri-Amin , T. Ohkubo , K. Hono , T. Schrefl

Noncollinear magnetic moments in antiferromagnets (AFM) lead to a complex behavior of electrical transport, even to a decreasing resistivity due to an increasing temperature. Proper treatment of such phenomena is required for understanding…

Materials Science · Physics 2020-06-19 David Wagenknecht , Karel Výborný , Karel Carva , Ilja Turek

A study of dynamic and reversible voltage controlled magnetization switching in ferromagnetic Co/Pt thin film with perpendicular magnetic anisotropy at room temperature is presented. The change in the magnetic properties of the system is…

Diluted Ising antiferromagnets in a homogenous magnetic field have a disordered phase for sufficiently large values of the field and for low temperatures. Here, the system is in a domain state with a broad size-distribution of fractal…

Disordered Systems and Neural Networks · Physics 2008-02-03 M. Staats , U. Nowak , K. D. Usadel

We consider the effects of the magnetic field on the frustrated phase states of the dilute Ising chain, especially, the behavior of the magnetic entropy change and the isentropic dependence of the temperature on the magnetic field, which…

Statistical Mechanics · Physics 2023-01-30 A. V. Shadrin , Yu. D. Panov

We study the symmetry breaking phenomenon in the standard model during the electroweak phase transition in the presence of a constant hypermagnetic field. We compute the finite temperature effective potential up to the contribution of ring…

High Energy Physics - Theory · Physics 2008-11-26 Angel Sanchez , Alejandro Ayala , Gabriella Piccinelli

Energy-efficient switching of nanoscale magnets requires the application of a time-varying magnetic field characterized by microwave frequency. At finite temperatures, even weak thermal fluctuations create perturbations in the magnetization…

Mesoscale and Nanoscale Physics · Physics 2023-12-19 Mohammad H. A. Badarneh , Grzegorz J. Kwiatkowski , Pavel F. Bessarab

We analyze the finite temperature phase diagram of ultrathin magnetic films by introducing a mean field theory, valid in the low anisotropy regime, i.e., close to de Spin Reorientation Transition. The theoretical results are compared with…

Statistical Mechanics · Physics 2015-06-11 Santiago A. Pighin , Orlando V. Billoni , Sergio A. Cannas

In the paper a study of a model magnetoelastic solid system is presented. The system of interest is a mean-field magnet with nearest-neighbour ferromagnetic interactions and the underlying s.c. crystalline lattice with the long-range Morse…

Statistical Mechanics · Physics 2017-09-15 K. Szałowski , T. Balcerzak , M. Jaščur

Assuming that the timescale of the magnetic field decay is approximately equal to that of the stellar cooling via neutrino emission, we obtain a one-to-one relationship between the effective surface thermal temperature and the inner…

High Energy Astrophysical Phenomena · Physics 2013-12-09 Z. F. Gao , N. Wang , Q. H. Peng

We study numerically the thermodynamic properties of the spin nematic phases in a magnetic field in the spin-1 bilinear-biquadratic model. When the field is applied, the phase transition temperature once goes up and then decreases rapidly…

Strongly Correlated Electrons · Physics 2020-10-14 Katsuhiro Tanaka , Chisa Hotta

Within the framework of the effective-field theory with correlations we investigate effects of an external magnetic field and random site dilution on basic thermodynamic quantities, such as the magnetization and the magnetic susceptibility,…

Statistical Mechanics · Physics 2023-07-19 M. Borovský , M. Žukovič , A. Bobák