Three-and two-dimensional calculations for the interface anisotropy dependence of magnetic properties of exchange-spring Nd2Fe(14)B/α-Fe multilayers with out-of-plane easy axes  

作　　者：Qian Zhao Xin-Xin He Francois-Jacques Morvan Guo-Ping Zhao Zhu-Bai Li 赵倩;何鑫鑫;李文瀚;赵国平;李柱柏(Inner Mongolia Key Laboratory for Utilization of Bayan Obo Multi-Metallic Resources,Elected State Key Laboratory,Department of Applied Physics,College of Science,Inner Mongolia University of Science and Technology,Baotou 014010,China;Ningbo Institute of Industrial Technology,Chinese Academy of Sciences,Ningbo 315201,China;College of Physics and Electronic Engineering,Sichuan Normal University,Chengdu 610066,China)

机构地区：[1]Inner Mongolia Key Laboratory for Utilization of Bayan Obo Multi-Metallic Resources,Elected State Key Laboratory,Department of Applied Physics,College of Science,Inner Mongolia University of Science and Technology,Baotou 014010,China [2]Ningbo Institute of Industrial Technology,Chinese Academy of Sciences,Ningbo 315201,China [3]College of Physics and Electronic Engineering,Sichuan Normal University,Chengdu 610066,China

出　　处：《Chinese Physics B》2020年第3期389-395,共7页中国物理B（英文版）

基　　金：Project supported by the National Key Research and Development Program of China(Grant No.2016YFB0700900);the National Natural Science Foundation of China(Grant Nos.51571126 and 51861030);the Inner Mongolia Autonomous Region Natural Science Foundation of China(Grant No.2019MS01002);the Inner Mongolia Innovative Research Team of China(Grant No.3400102)。

摘　　要：Hysteresis loops,energy products and magnetic moment distributions of perpendicularly oriented Nd2Fe(14)B/α-Fe exchange-spring multilayers are studied systematically based on both three-dimensional(3D)and one-dimensional(1D)micromagnetic methods,focused on the influence of the interface anisotropy.The calculated results are carefully compared with each other.The interface anisotropy effect is very palpable on the nucleation,pinning and coercive fields when the soft layer is very thin.However,as the soft layer thickness increases,the pinning and coercive fields are almost unchanged with the increment of interface anisotropy though the nucleation field still monotonically rises.Negative interface anisotropy decreases the maximum energy products and increases slightly the angles between the magnetization and applied field.The magnetic moment distributions in the thickness direction at various applied fields demonstrate a progress of three-step magnetic reversal,i.e.,nucleation,evolution and irreversible motion of the domain wall.The above results calculated by two models are in good agreement with each other.Moreover,the in-plane magnetic moment orientations based on two models are different.The 3D calculation shows a progress of generation and disappearance of vortex state,however,the magnetization orientations within the film plane calculated by the 1D model are coherent.Simulation results suggest that negative interface anisotropy is necessarily avoided experimentally.Hysteresis loops, energy products and magnetic moment distributions of perpendicularly oriented Nd2Fe14B/α-Fe exchange-spring multilayers are studied systematically based on both three-dimensional（3D） and one-dimensional（1D）micromagnetic methods, focused on the influence of the interface anisotropy. The calculated results are carefully compared with each other. The interface anisotropy effect is very palpable on the nucleation, pinning and coercive fields when the soft layer is very thin. However, as the soft layer thickness increases, the pinning and coercive fields are almost unchanged with the increment of interface anisotropy though the nucleation field still monotonically rises. Negative interface anisotropy decreases the maximum energy products and increases slightly the angles between the magnetization and applied field.The magnetic moment distributions in the thickness direction at various applied fields demonstrate a progress of three-step magnetic reversal, i.e., nucleation, evolution and irreversible motion of the domain wall. The above results calculated by two models are in good agreement with each other. Moreover, the in-plane magnetic moment orientations based on two models are different. The 3D calculation shows a progress of generation and disappearance of vortex state, however, the magnetization orientations within the film plane calculated by the 1D model are coherent. Simulation results suggest that negative interface anisotropy is necessarily avoided experimentally.

关 键 词：MICROMAGNETICS interface anisotropy Nd2Fe(14)B/α-Fe MULTILAYERS MAGNETIC properties 

分 类 号：TB34[一般工业技术—材料科学与工程] O469[理学—凝聚态物理]