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Related papers: A model for vortex formation in magnetic nanodots

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We use Monte Carlo simulations to study the finite temperature behavior of vortices in the XY- model for tangent vector order on curved backgrounds. Contrary to naive expectations, we show that the underlying geometry does not affect the…

Statistical Mechanics · Physics 2018-01-24 Leopoldo R. Gómez , Nicolás A. García , Daniel A. Vega , José Lorenzana

We investigate the magnetization dynamics in nanomagnet vertices often found in artificial spin ices. Our analysis involves creating a simplified model that depicts edge magnetization using magnetic charges. We utilize the model to explore…

Mesoscale and Nanoscale Physics · Physics 2024-07-15 Samuel D. Slöetjes , Matías P. Grassi , Vassilios Kapaklis

The magnetic relaxation and hysteresis of a system of single domain particles with dipolar interactions are studied by Monte Carlo simulations. We model the system by a chain of Heisenberg classical spins with randomly oriented easy-axis…

Materials Science · Physics 2007-05-23 Oscar Iglesias , Amilcar Labarta

We present results of micromagnetic simulations of thin ferromagnetic nano hemispheroidal shells with sizes ranging from 1 to 50 nm (inside dimensions). Depending on the geometrical and magnetic parameters of the hemispheroidal shell, there…

Mesoscale and Nanoscale Physics · Physics 2017-08-23 Keren Schultz , Moty Schultz

We report a Monte Carlo study of the classical antiferromagnetic Heisenberg model with easy axis anisotropy on the triangular lattice. Both the free energy cost for long wavelength spin waves as well as for the formation of free vortices…

Statistical Mechanics · Physics 2009-10-31 W. Stephan , B. W. Southern

We study the Heisenberg Model on cylindrically symmetric curved surfaces. Two kinds of excitations are considered. The first is given by the isotropic regime, yielding the sine-Gordon equation and $\pi$-solitons are predicted. The second…

Mesoscale and Nanoscale Physics · Physics 2013-03-27 Vagson L. Carvalho-Santos , Felipe A. Apolonio , Nemésio M. Oliveira-Neto

Determination of a magnetic field structure on a neutron star (NS) surface is an important problem of a modern astrophysics. In a presence of strong magnetic fields a thermal conductivity of a degenerate matter is anisotropic. In this paper…

High Energy Astrophysical Phenomena · Physics 2020-08-05 Ilya A. Kondratyev , Sergey G. Moiseenko , Gennady S. Bisnovatyi-Kogan , Maria V. Glushikhina

We apply the Halperin-Mazenco formalism within the Gross-Pitaevskii theory to characterise the kinematics and nucleation of quantum vortices in a two-dimensional stirred Bose Einstein condensate. We introduce a smooth defect density field…

Quantum Gases · Physics 2022-10-27 Jonas Rønning , Luiza Angheluta

Formation of a magnetic hysteresis loop with respect to a bias voltage is investigated theoretically in a spin-valve device based on a single magnetic molecule. We consider a device consisting of two ferromagnetic electrodes bridged by a…

Mesoscale and Nanoscale Physics · Physics 2018-05-09 Anna Płomińska , Maciej Misiorny , Ireneusz Weymann

Magnetic nanostructures are often considered as highly functional materials because they exhibit unusual magnetic properties under different external conditions. We study the effect of surface pinning on the core-shell magnetic…

Mesoscale and Nanoscale Physics · Physics 2020-02-19 Aditi Sahoo , Dipten Bhattacharya , P. K. Mohanty

A model for describing structural pointlike defects in nanoscaled ferromagnetic materials is presented. Its details are explicitly developed whenever interacting with a vortex-like state comprised in a thin nanodisk. Among others, our model…

Mesoscale and Nanoscale Physics · Physics 2011-08-05 F. A. Apolonio , W. A. Moura-Melo , F. P. Crisafulli , A. R. Pereira , R. L. Silva

We have used Monte Carlo simulations to investigate the magnetic properties of asymmetric dots as a function of their geometry. The asymmetry of round dots is produced by cutting off a fraction of the dot and is characterized by an…

Mesoscale and Nanoscale Physics · Physics 2011-06-08 N. M. Vargas , S. Allende , B. Leighton , J. Escrig , J. Mejía-López , D. Altbir , Ivan K. Schuller

Recent work [1] demonstrated high coercivity and magnetic moment in cobalt carbide nanoparticle assemblies and explained the high coercivity from first principles in terms of the high magnetocrystalline anisotropy of the cobalt carbide…

Mesoscale and Nanoscale Physics · Physics 2018-09-26 Pallabi Sutradhar , Shiv N. Khanna , Jayasimha Atulasimha

Co-based nanostructures ranging from core-shell to hollow nanoparticles were produced by varying the reaction time and the chemical environment during the thermal decomposition of Co2(CO)8. Both structural characterization and kinetic model…

Developing permanent magnets with fewer critical elements requires understanding hysteresis effects and coercivity through visualizing magnetization reversal. Here, we numerically investigate the effect of the geometry of nanoscale…

Materials Science · Physics 2025-08-27 Shouvik Sarker , Md Mahadi Rajib , Radhika Barua , Jayasimha Atulasimha

Highly sophisticated synthesis methods and experimental techniques allow for precise measurements of magnetic properties of nanoparticles that can be reliably reproduced using theoretical models. Here, we investigate the magnetic properties…

Mesoscale and Nanoscale Physics · Physics 2022-09-21 Nikolaos Ntallis , Corisa Kons , Hariharan Srikanth , Manh-Huong Phan , D. A. Arena , Manuel Pereiro

We developed a micromagnetic method for modeling magnetic systems with periodic boundary conditions along an arbitrary number of dimensions. The main feature is an adaptation of the Ewald summation technique for evaluation of long-range…

Mesoscale and Nanoscale Physics · Physics 2015-10-30 Aleksander L. Wysocki , Vladimir P. Antropov

We study the effective anisotropy induced in thin nanomagnets by the nonlocal demagnetization field (dipole-dipole interaction). Assuming a magnetization independent of the thickness coordinate, we reduce the energy to an inhomogeneneous…

Strongly Correlated Electrons · Physics 2008-01-29 Jean-Guy Caputo , Yuri Gaididei , Volodymyr P. Kravchuk , Franz G. Mertens , Denis D. Sheka

We study the finite-size and surface effects on the thermal and spatial behaviors of the magnetisation of a small magnetic particle. We consider two systems: 1) A box-shaped isotropic particle of simple cubic structure with either periodic…

Materials Science · Physics 2009-10-31 H. Kachkachi , M. Nogues , E. Tronc , D. A. Garanin

We perform computer simulations to probe the magnetic hysteresis in a two-dimensional ($L^{}_x\times L^{}_y$) assembly of magnetic nanoparticles as a function of dipolar interaction strength $h^{}_d$, temperature $T$, aspect ratio…

Materials Science · Physics 2021-09-14 Manish Anand