Inverse giant magnetoresistance in Fe/Cu/Gd1-xCox spin-valves

被引:23
作者
Yang, D. Z.
You, B.
Zhang, X. X.
Gao, T. R.
Zhou, S. M. [1 ]
Du, J.
机构
[1] Fudan Univ, Surface Phys Lab, State Key Lab, Shanghai 200433, Peoples R China
[2] Fudan Univ, Dept Phys, Shanghai 200433, Peoples R China
[3] Hong Kong Univ Sci & Technol, Dept Phys, Kowloon, Hong Kong, Peoples R China
[4] Nanjing Univ, State Key Lab Solid Microstruct, Nanjing 210093, Peoples R China
关键词
D O I
10.1103/PhysRevB.74.024411
中图分类号
T [工业技术];
学科分类号
08 ;
摘要
For bottom spin-valves of NiO/Fe/Cu/Gd1-xCox, giant magnetoresistance has been measured as a function of thickness and composition of GdCo layers as well as temperature. For all spin-valves involved here, the giant magnetoresistance has been attributed to contributions of spin-dependent scattering at interfaces and in bulk. The interfacial contribution produces positive giant magnetoresistance ratio for various compositions of GdCo alloys. However, the bulk contribution produces negative one for the Co contents from 50 at. % to a critical value x(C)(R) (between 69 at. % and 77 at. %) and positive one for higher Co contents. It is suggested that the interfacial asymmetric factor of spin-dependent scattering is larger than 1.0 at the Cu/GdCo for various alloy compositions of GdCo and that the bulk asymmetric factor in GdCo layer is smaller and larger than 1.0 for Co contents below and above x(C)(R), respectively. For spin valves with Co contents below and/or above x(C)(R), the giant magnetoresistance ratio varies nonmonotonically and/or monotonically as a function of the GdCo layer thickness (temperature) for a specific temperature (a specific GdCo layer thickness), respectively. The change of the bulk asymmetric factor in the GdCo layer with the alloy composition can be attributed to the variation of either the spin alignment of Co and Gd atoms or the spin polarization of the GdCo layer.
引用
收藏
页数:6
相关论文
共 21 条
[1]   NOVEL MAGNETORESISTANCE EFFECT IN LAYERED MAGNETIC-STRUCTURES - THEORY AND EXPERIMENT [J].
BARNAS, J ;
FUSS, A ;
CAMLEY, RE ;
GRUNBERG, P ;
ZINN, W .
PHYSICAL REVIEW B, 1990, 42 (13) :8110-8120
[2]   Influence of the thickness of the CoFe layer on the negative spin-valve effect in CoFe/Ag/CoFeGd trilayers [J].
Bellouard, C ;
George, B ;
Marchal, G ;
Maloufi, N ;
Eugene, J .
JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS, 1997, 165 (1-3) :312-315
[3]   Negative spin-valve effect in Co65Fe35/Ag/(Co65Fe35)(50)Gd-50 trilayers [J].
Bellouard, C ;
Rapp, HD ;
George, B ;
Mangin, S ;
Marchal, G ;
Ousset, JC .
PHYSICAL REVIEW B, 1996, 53 (09) :5082-5085
[4]   Quantitative interpretation of the magnetoresistive response (amplitude and shape) of spin valves with synthetic antiferromagnetic pinned layers [J].
Dieny, B ;
Li, M ;
Liao, SH ;
Horng, C ;
Ju, K .
JOURNAL OF APPLIED PHYSICS, 2000, 87 (07) :3415-3420
[5]   INVERSE SPIN-VALVE-TYPE MAGNETORESISTANCE IN SPIN ENGINEERED MULTILAYERED STRUCTURES [J].
GEORGE, JM ;
PEREIRA, LG ;
BARTHELEMY, A ;
PETROFF, F ;
STEREN, L ;
DUVAIL, JL ;
FERT, A ;
LOLOEE, R ;
HOLODY, P ;
SCHROEDER, PA .
PHYSICAL REVIEW LETTERS, 1994, 72 (03) :408-411
[6]   MAGNETIC AND MAGNETO-OPTICAL PROPERTIES OF RARE-EARTH TRANSITION-METAL ALLOYS CONTAINING GD, TB, FE, CO [J].
HANSEN, P ;
CLAUSEN, C ;
MUCH, G ;
ROSENKRANZ, M ;
WITTER, K .
JOURNAL OF APPLIED PHYSICS, 1989, 66 (02) :756-767
[7]   TEMPERATURE-DEPENDENCE OF THE NORMAL AND INVERSE MAGNETORESISTANCE IN MAGNETIC MULTILAYERS [J].
HASEGAWA, H .
PHYSICAL REVIEW B, 1995, 51 (06) :3655-3659
[8]   Towards a unified picture of spin dependent transport in and perpendicular giant magnetoresistance and bulk alloys [J].
Hsu, SY ;
Barthelemy, A ;
Holody, P ;
Loloee, R ;
Schroeder, PA ;
Fert, A .
PHYSICAL REVIEW LETTERS, 1997, 78 (13) :2652-2655
[9]   Finite tunneling spin polarization at the compensation point of rare-earth-metal-transition-metal alloys [J].
Kaiser, C ;
Panchula, AF ;
Parkin, SSP .
PHYSICAL REVIEW LETTERS, 2005, 95 (04)
[10]   Positive giant magnetoresistance in ferrimagnetic/Cu/ferrimagnetic films [J].
Lai, CH ;
Lin, CC ;
Chen, BM ;
Shieh, HPD ;
Chang, CR .
JOURNAL OF APPLIED PHYSICS, 2001, 89 (11) :7124-7126