Magnetoresistance of FeCo nanocontacts with current-perpendicular-to-plane spin-valve structure

被引：44

作者：

Fuke, Hiromi Niu ^{[1
]}

Hashimoto, Susumu

Takagishi, Masayuki

Iwasaki, Hitoshi

Kawasaki, Shohei

Miyake, Kousaku

Sahashi, Masashi

机构：

[1] Toshiba Co Ltd, Corp Res & Dev Ctr, Kawasaki, Kanagawa 2128582, Japan

[2] Tohoku Univ, Dept Elect Engn, Grad Sch Engn, Sendai, Miyagi 9808579, Japan

来源：

IEEE TRANSACTIONS ON MAGNETICS | 2007年 / 43卷 / 06期

关键词：

conductive atomic-force-microscopy; domain wall; nanocontact magnetoresistance (MR); spin-valve;

D O I：

10.1109/TMAG.2007.893117

中图分类号：

TM [电工技术]; TN [电子技术、通信技术];

学科分类号：

0808 ; 0809 ;

摘要：

We have achieved a magnetoresistance (MR) ratio of 7%-10% at a resistance area product (RA) of 0.5-1.5 Omega mu m(2) by ferromagnetic FeCo nanocontacts in Al nano-oxide-layer (NOL) with current-perpendicular-to-plane spin-valve (CPP-SV) structure. Conductive atomic-force-microscopy shows clear current-path regions of a few nanometers in size surrounded by the Al-NOL. The MR dependence on resistance area product (RA) is well explained by the current-confined-path model assuming that the spin-dependent scattering has an FeCo nanocontact origin, different from tunnel magnetoresistance (TMR). Resistance increases with increasing bias voltage, indicating joule heating by high-current density in nanocontacts, in contrast to TMR. The MR origin is mainly interpreted as spin-dependent scattering due to domain wall formed at ferromagnetic nanocontact.

引用

页码：2848 / 2850

页数：3

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