Quantitative measurement of voltage dependence of spin-transfer torque in MgO-based magnetic tunnel junctions

被引：474

作者：

Kubota, Hitoshi ^{[1
]}

Fukushima, Akio ^{[1
]}

Yakushiji, Kay ^{[1
]}

Nagahama, Taro ^{[1
]}

Yuasa, Shinji ^{[1
]}

Ando, Koji ^{[1
]}

Maehara, Hiroki ^{[2
]}

Nagamine, Yoshinori ^{[2
]}

Tsunekawa, Koji ^{[2
]}

Djayaprawira, David D. ^{[2
]}

Watanabe, Naoki ^{[2
]}

Suzuki, Yoshishige ^{[1
,3
]}

机构：

[1] Nanoelect Res Inst, Natl Inst Adv Ins Sci & Technol, Tsukuba, Ibaraki 3058568, Japan

[2] Canon ANELVA Corp, Elect Device Div, Tokyo 1838508, Japan

[3] Osaka Univ, Grad Sch Engn Sci, Osaka 5608531, Japan

来源：

NATURE PHYSICS | 2008年 / 4卷 / 01期

基金：

日本学术振兴会;

关键词：

D O I：

10.1038/nphys784

中图分类号：

O4 [物理学];

学科分类号：

0702 ;

摘要：

When an electric current passes from one ferromagnetic layer via a non-magnetic layer into another ferromagnetic layer, the spin polarization and subsequent rotation of this current can induce a transfer of angular momentum that exerts a torque on the second ferromagnetic layer(1-4). This provides a potentially useful method to reverse(3,5-7) and oscillate(8) the magnetic momenta in nanoscale magnetic structures. Owing to the large current densities required to observe spin-torque-induced magnetization switching and microwave emission (similar to 10(7) A cm(-2)), accurately measuring the strength, or even the direction, of the associated spin torque has proved difficult. Yet, such measurements are crucial to refining our understanding of the mechanisms responsible and the theories that describe them(9,10). To address this, we present quantitative experimental measurements of the spin torque in MgO-based magnetic tunnel junctions(11-14) for a wide range of bias currents covering the switching currents. The results verify the occurrence of two different spin-torque regimes with different bias dependences that agree well with theoretical predictions(10).

引用

页码：37 / 41

页数：5

共 27 条

[1]

[Anonymous], 2007, IEEE INT SOLID STATE

[2] Emission of spin waves by a magnetic multilayer traversed by a current [J].

Berger, L .

PHYSICAL REVIEW B, 1996, 54 (13) :9353-9358

[3] Spin-dependent tunneling conductance of Fe|MgO|Fe sandwiches -: art. no. 054416 [J].

Butler, WH ;

Zhang, XG ;

Schulthess, TC ;

MacLaren, JM .

PHYSICAL REVIEW B, 2001, 63 (05)

[4] Spin transfer switching and spin polarization in magnetic tunnel junctions with MgO and AlOx barriers -: art. no. 232502 [J].

Diao, Z ;

Apalkov, D ;

Pakala, M ;

Ding, YF ;

Panchula, A ;

Huai, YM .

APPLIED PHYSICS LETTERS, 2005, 87 (23) :1-3

[5] 230% room-temperature magnetoresistance in CoFeB/MgO/CoFeB magnetic tunnel junctions [J].

Djayaprawira, DD ;

Tsunekawa, K ;

Nagai, M ;

Maehara, H ;

Yamagata, S ;

Watanabe, N ;

Yuasa, S ;

Suzuki, Y ;

Ando, K .

APPLIED PHYSICS LETTERS, 2005, 86 (09) :1-3

[6] Spin-transfer effects in nanoscale magnetic tunnel junctions [J].

Fuchs, GD ;

Emley, NC ;

Krivorotov, IN ;

Braganca, PM ;

Ryan, EM ;

Kiselev, SI ;

Sankey, JC ;

Ralph, DC ;

Buhrman, RA ;

Katine, JA .

APPLIED PHYSICS LETTERS, 2004, 85 (07) :1205-1207

[7] Current-driven magnetization switching in CoFeB/MgO/CoFeB magnetic tunnel junctions [J].

Hayakawa, J ;

Ikeda, S ;

Lee, YM ;

Sasaki, R ;

Meguro, T ;

Matsukura, F ;

Takahashi, H ;

Ohno, H .

JAPANESE JOURNAL OF APPLIED PHYSICS PART 2-LETTERS & EXPRESS LETTERS, 2005, 44 (37-41) :L1267-L1270

[8]

Hosomi M, 2005, INT EL DEVICES MEET, P473

[9] Observation of spin-transfer switching in deep submicron-sized and low-resistance magnetic tunnel junctions [J].

Huai, YM ;

Albert, F ;

Nguyen, P ;

Pakala, M ;

Valet, T .

APPLIED PHYSICS LETTERS, 2004, 84 (16) :3118-3120

[10] Microwave oscillations of a nanomagnet driven by a spin-polarized current [J].

Kiselev, SI ;

Sankey, JC ;

Krivorotov, IN ;

Emley, NC ;

Schoelkopf, RJ ;

Buhrman, RA ;

Ralph, DC .

NATURE, 2003, 425 (6956) :380-383

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