Micromagnetic simulation of vortex-antivortex magnetization in permalloy nano particle

International Conference on Advanced Materials for Better Future 2016

Purnama, B.^1 ; Muhammady, S.^1 ; Suharyana^1

Department of Physics, Faculty of Mathematics and Natural Sciences, Universitas Sebelas Maret, Jl. Ir. Sutami 36A, Kentingan Surakarta

57126, Indonesia^1

关键词: Barrier energy;    Creation-annihilation process;    Landau-Lifshitz-Gilbert equations;    Magnetization direction;    Micromagnetic simulations;    Reversal mechanism;    Threshold-value;    Vortex-antivortex pairs;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/176/1/012050/pdf
DOI  :  10.1088/1757-899X/176/1/012050

来源: IOP

【 摘 要 】

A process of vortex-antivortex magnetization reversal in a Permalloy nano particle with uniform polarity of magnetization has been investigated numerically. Micromagnetic simulation is performed using the Landau-Lifshitz-Gilbert equation. A short field pulse is applied in a film plane anti parallel to magnetization direction. Sequences of simulation of reversals mechanism are evaluated for thickness of nano particle. As the results in the case of thickness of 20 nm thin layer, magnetization reversal realizes through a creation-annihilation of Neel-Bloch wall pair. Contrarily, reversal mechanism via a creation-annihilation process of vortex-antivortex pair occurs for thickness of 60 nm thin layer. By analyzing barrier energy of the sample, we find that a maximum barrier energy reaches a threshold value (e.g., ∼ 2.6×106erg/cm3for Permalloy in this simulation).