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Related papers: Analytic Expression for Magnetic Activation Energy

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I present the exact analytical expression for the activation energy as a function of externally applied magnetic fields for a single--domain magnetic particle with uniaxial anisotropy (Stoner--Wohlfahrt model), and investigate the scaling…

Mesoscale and Nanoscale Physics · Physics 2009-11-13 Daniel Braun

A formula for the magnetostatic energy of a finite magnet is proven. In contrast to common approaches, the new energy identity does not rely on evaluation of a nonlocal boundary integral inside the magnet or the solution of an equivalent…

Computational Physics · Physics 2018-08-02 Lukas Exl

We derive an exact expression for the orbital magnetization of electrons with short-range interactions (such as density-density interactions) in terms of exact zero-frequency response functions of the zero-field system. The result applies…

Strongly Correlated Electrons · Physics 2026-02-03 Xi Chen , Zhi-Da Song

We study the energy levels of H$_2$ molecules in a superstrong magnetic field ($B\go 10^{12}$ G), typically found on the surfaces of neutron stars. The interatomic interaction potentials are calculated by a Hartree-Fock method with…

Astrophysics · Physics 2009-10-28 Dong Lai , Edwin E. Salpeter

We obtain explicit expressions for thermodynamic quantities of a relativistic degenerate free electron gas in a magnetic field in terms of Hurwitz Zeta functions. The formulation allows for systematic expansion in all regimes. Three energy…

Mathematical Physics · Physics 2009-10-31 Claudio O. Dib , Olivier R. Espinosa

We study interacting electrons in a periodic potential and a uniform magnetic field ${\bf B}$ taking the spin-orbit interaction into account. We first establish a perturbation expansion for those electrons with respect to the Bloch states…

Materials Science · Physics 2009-11-11 Takafumi Kita , Masao Arai

We self-consistently derive the magnetic energy and relative magnetic helicity budgets of a three-dimensional linear force-free magnetic structure rooted in a lower boundary plane. For the potential magnetic energy we derive a general…

Astrophysics · Physics 2009-11-13 M. K. Georgoulis , Barry J. LaBonte

Thermally activated flux flow and vortex glass transition of recently discovered SmFeAsO$_{0.9}$F$_{0.1}$ superconductor are studied in magnetic fields up to 9.0 T. The thermally activated energy is analyzed in two analytic methods, of…

Superconductivity · Physics 2015-05-13 Y. Z. Zhang , Z. A. Ren , Z. X. Zhao

The recent development in the field of 2D magnetic materials urges reliable theoretical methodology for determination of magnetic properties. Among the available methods, ab initio four-state energy mapping based on Density Functional…

Mesoscale and Nanoscale Physics · Physics 2020-08-05 Denis Sabani , Cihan Bacaksiz , Milorad Milosevic

Based on standard perturbation theory, we present a full quantum derivation of the formula for the orbital magnetization in periodic systems. The derivation is generally valid for insulators with or without a Chern number, for metals at…

Mesoscale and Nanoscale Physics · Physics 2009-11-13 Junren Shi , G. Vignale , Di Xiao , Qian Niu

In this paper we present a method to accurately compute the energy of the magnetostatic interaction between linearly (or uniformly, as a special case) magnetized polyhedrons. The method has applications in finite element micromagnetics, or…

Computational Physics · Physics 2016-07-14 Dmitri Chernyshenko , Hans Fangohr

The coercive field of permanent magnets decays with temperature. At non-zero temperature the system can overcome a finite energy barrier through thermal fluctuations. Using finite element micromagnetic simulations, we quantify this effect,…

Materials Science · Physics 2016-03-29 Simon Bance , Johann Fischbacher , Alexander Kovacs , Harald Oezelt , Franz Reichel , Thomas Schrefl

We construct a semiclassical theory for electrons in a non-Hermitian periodic system subject to perturbations varying slowly in space and time. We derive the energy of the wavepacket to first order in the gradients of the perturbations.…

Mesoscale and Nanoscale Physics · Physics 2026-04-28 Bar Alon , Moshe Goldstein , Roni Ilan

In this paper, the energy eigenvalues of the two dimensional hydrogen atom are presented for the arbitrary Larmor frequencies by using the asymptotic iteration method. We first show the energy eigenvalues for the no magnetic field case…

Quantum Physics · Physics 2009-11-13 A. Soylu , O. Bayrak , I. Boztosun

The magnetogenesis scenarios triggered by the early variation of the gauge coupling are critically analyzed. In the absence of sources, it is shown that the electric and magnetic power spectra can be explicitly computed by means of…

Cosmology and Nongalactic Astrophysics · Physics 2010-04-29 Massimo Giovannini

We consider helical coupling to electromagnetism and present a simple scenario of evolution of the coupling function leading to a viable inflationary magnetogenesis without the problem of back-reaction. In this scenario, helical magnetic…

Cosmology and Nongalactic Astrophysics · Physics 2019-10-09 Yuri Shtanov

Direct expressions for the magnetic anisotropy constants are given at a finite temperature from microscopic viewpoints. In the present derivation, it is assumed that the Hamiltonian is a linear function with respect to the magnetization…

Materials Science · Physics 2015-10-26 Daisuke Miura , Ryo Sasaki , Akimasa Sakuma

Temperature-dependent magnetic properties of Nd$_2$Fe$_{14}$B permanent magnets, i.e., saturation magnetization $M_\text{s}(T)$, effective magnetic anisotropy constants $K_i^\text{eff}(T)$ ($i=1,2,3$), domain wall width $\delta_w(T)$, and…

Materials Science · Physics 2019-06-18 Qihua Gong , Min Yi , Richard F. L. Evans , Bai-Xiang Xu , Oliver Gutfleisch

Magnetic and magnetoelectric excitations in the multiferroic TbMnO_3 have been investigated at terahertz frequencies. Using different experimental geometries we can clearly separate the electro-active excitations (electromagnons) from the…

Strongly Correlated Electrons · Physics 2009-03-16 A. Pimenov , A. Shuvaev , A. Loidl , F. Schrettle , A. A. Mukhin , V. D. Travkin , V. Yu. Ivanov , A. M. Balbashov

We discuss the dynamics of a charged nonrelativistic particle in electromagnetic field of a rotating magnetized celestial body. The equations of motion of the particle are obtained and some particular solutions are found. Effective…

High Energy Astrophysical Phenomena · Physics 2013-08-08 V. Epp , M. A. Masterova
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