Morphology induced magnetoresistance enhancement of tunneling junctions with the Heusler electrode Co2Cr0.6Fe0.4Al

被引：22

作者：

Herbort, Christian ^{[1
]}

Jorge, Elena Arbelo ^{[1
]}

Jourdan, Martin ^{[1
]}

机构：

[1] Johannes Gutenberg Univ Mainz, Inst Phys, D-55128 Mainz, Germany

来源：

APPLIED PHYSICS LETTERS | 2009年 / 94卷 / 14期

关键词：

aluminium; aluminium compounds; chromium alloys; cobalt alloys; electrodes; electron spin polarisation; ferromagnetic materials; iron alloys; magnetic thin films; magnetoresistance; metallic thin films; oxidation; scanning tunnelling microscopy; tunnelling magnetoresistance; wetting; ROOM-TEMPERATURE; ALLOYS; FILMS;

D O I：

10.1063/1.3114425

中图分类号：

O59 [应用物理学];

学科分类号：

摘要：

A large magnetoresistance is expected when half-metallic ferromagnets are used in magnetic tunneling junctions with polycrystalline AlOx barrier. We demonstrate by in situ tunneling microscopy how the atomically smooth morphology of Co2Cr0.6Fe0.4Al Heusler thin films results in unfavorable wetting properties of the Al layer, which forms the tunneling barrier after oxidation. The insertion of a very thin (2.5 A) Mg layer at the Co2Cr0.6Fe0.4Al/Al interface changes the growth mode of the Al drastically. As a result the tunneling magnetoresistance (TMR) is clearly enhanced [Co2Cr0.6Fe0.4Al/AlOx/Co70Fe30 junction: TMR(4 K)=101%]. The corresponding Julliere spin polarization amounts to 67%, larger than previously reported values for this compound.

引用

页数：3

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