Spin-transfer-induced microwave oscillations in spin valves with ferromagnetic nano-contacts in oxide spacer layer

被引：12

作者：

Doi, Masaaki ^{[1
]}

Endo, Hiroaki ^{[1
]}

Shirafuji, Kazushige ^{[1
]}

Kawasaki, Shohei ^{[1
]}

Sahashi, Masashi ^{[1
]}

Fuke, Hiromi Niu ^{[2
]}

Iwasaki, Hitoshi ^{[2
]}

Imamura, Hiroshi ^{[3
]}

机构：

[1] Tohoku Univ, Grad Sch Engn, Dept Elect Engn, Aoba Ku, Sendai, Miyagi 9808579, Japan

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

[3] AIST, Nanosyst Res Inst, Tsukuba, Ibaraki 3058568, Japan

来源：

JOURNAL OF PHYSICS D-APPLIED PHYSICS | 2011年 / 44卷 / 09期

关键词：

CURRENT-CONFINED-PATH; PHASE-LOCKING; MAGNETORESISTANCE; DRIVEN;

D O I：

10.1088/0022-3727/44/9/092001

中图分类号：

O59 [应用物理学];

学科分类号：

摘要：

We observed microwave oscillations induced by spin-transfer torque in spin valves with ferromagnetic nano-contacts in oxide spacer layer near the antiparallel magnetic moment configuration between the free and the reference layers. The frequency of the microwave oscillation ranges from 4.2 to 9.7 GHz and the Q-value of the level peak reaches as high as around 300. We showed that the frequency of the oscillation depends on the applied current and magnetic field, which can be qualitatively explained by considering the response of the domain walls confined in nano-contacts to the applied current and magnetic field.

引用

页数：4

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