新型反铁磁/稀释反铁磁型异质结构的交换偏置效应研究

项目名称： 新型反铁磁/稀释反铁磁型异质结构的交换偏置效应研究

项目编号： No.11304098

项目类型： 青年科学基金项目

立项/批准年度： 2014

项目学科： 数理科学和化学

项目作者： 毛忠泉

作者单位： 华南理工大学

项目金额： 25万元

中文摘要： 磁记录是信息存储中最重要的技术手段。交换偏置效应是现代高密度磁记录及未来超高密度磁记录的关键物理基础之一。近年来，多种新型交换偏置体系的发现促使人们重新思考该效应背后的物理本质。反铁磁(AFM)/稀释反铁磁(DAF)核/壳纳米结构材料是最近备受关注的一种具有交换偏置效应的磁性系统，并有望在新型磁电耦合记录领域获得重要应用。然而，目前的研究大都基于宏观磁性的实验测量，难以排除尺寸效应和DAF冻结磁矩的影响，因此存在很大争议。同时，在该结构中交换偏置效应的微观机理也缺乏相应的理论研究。本项目将以Monte Carlo微磁学计算为主要手段, 从宏观磁性计算和微观自旋构型模拟两方面入手，系统地研究AFM/DAF异质结构的交换偏置效应、尺寸效应和DAF冻结磁矩效应, 深入探索交换偏置效应的微观机理。

中文关键词： 交换偏置效应；磁性纳米颗粒；磁性材料；异质结构；稀释反铁磁

英文摘要： Magnetic recording is now the most significant technology in information storage. The exchange bias (EB)effect is a cornerstone of the modern high density magnetic recording technology and the next generation ultra-high density magnetic storage technology. Recently, EB is observed in new systems，stimulating new consideration of the underlying physics of EB. The antiferromagnet(AFM)/diluted antiferromagnet (DAF) heterostructure is among those systems and proposed great application potential in the magnetoelectric coupling recording medium. However, most of the researches now focus on the macroscopic magnetic properties measurements, which do not distinguish the EB effect from other effects. Meanwhile the microscopic mechanism of EB in such systems is scarce in literature as well. In this proposal, we plan to investigate systematically the EB behavior of the AFM/DAF heterostructures by means of Monte Carlo calculations. And we propose to study its microscopic mechanisms by comparing the macroscopic magnetic properties and microscopic spin configuration of the AFM/DAF heterostructures with that of the AFM or DAF single-phase meterials.

英文关键词： exchange bias effect；magnetic nanoparticles；magnetic materials；heterostructure；diluted antiferromagnet