Magnetization reversal mechanism of magnetic tunnel junctions

• 来源期刊: 中国物理（英文版）
• 学科: 物理学
• 关键词: tunnelling junction magnetoresistance spin-dependent scattering
• 年，卷（期）: 2002,（1）
• 页码范围: 66-71
• 页数: 6页
• 分类号: O4
• 语种: 英文

摘要

Using the ion-beam-sputtering technique, we have fabricated Fe/Al2O3/Fe magnetic tunnelling junctions (MTJs).We have observed double-peaked shapes of curves, which have a level summit and a symmetrical feature, showing themagnetoresistance of the junction as a function of applied field. We have measured the tunnel conductance of MTJswhich have insulating layers of different thicknesses. We have studied the dependence of the magnetoresistance ofMTJs on tunnel conductance. The microstructures of hard- and soft-magnetic layers and interfaces of ferromagnetsand insulators were probed.Analysing the influence of MJT microstructures, including those having clusters or/andgranules in magnetic and non-magnetic films, a magnetization reversal mechanism (MRM) is proposed, which suggeststhat the MRM of tunnelling junctions may be explained by using a group-by-group reversal model of magnetic momentsof the mesoscopical particles. We discuss the influence of MTJ microstructures, including those with clusters or/andgranules in the ferromagnetic and non-magnetic films, on the MRM.