Asymmetric angular dependence of spin-transfer torques in CoFe/Mg-B-O/CoFe magnetic tunnel junctions

Journal Article · Thu Apr 28 04:00:00 EDT 2016 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.4947527· OSTI ID:22594644

Tang, Ling; Xu, Zhi-Jun; Zuo, Xian-Jun; Yang, Ze-Jin ^[1]; Gao, Qing-He ^[2]; Linghu, Rong-Feng ^[3]; Guo, Yun-Dong ^[4]

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1. Department of Applied Physics, College of Science, Zhejiang University of Technology, Hangzhou 310023 (China)
2. College of Science, Northeastern University, Shenyang 110004, China, Information Engineering College, Liaoning University of Traditional Chinese Medicine, Shenyang 110847 (China)
3. School of Physics and Electronics Sciences, Guizhou Education University, Guiyang 550018 (China)
4. College of Engineering and Technology, Neijiang Normal University, Neijiang 641112 (China)

Using a first-principles noncollinear wave-function-matching method, we studied the spin-transfer torques (STTs) in CoFe/Mg-B-O/CoFe(001) magnetic tunnel junctions (MTJs), where three different types of B-doped MgO in the spacer are considered, including B atoms replacing Mg atoms (Mg{sub 3}BO{sub 4}), B atoms replacing O atoms (Mg{sub 4}BO{sub 3}), and B atoms occupying interstitial positions (Mg{sub 4}BO{sub 4}) in MgO. A strong asymmetric angular dependence of STT can be obtained both in ballistic CoFe/Mg{sub 3}BO{sub 4} and CoFe/Mg{sub 4}BO{sub 4} based MTJs, whereas a nearly symmetric STT curve is observed in the junctions based on CoFe/Mg{sub 4}BO{sub 3}. Furthermore, the asymmetry of the angular dependence of STT can be suppressed significantly by the disorder of B distribution. Such skewness of STTs in the CoFe/Mg-B-O/CoFe MTJs could be attributed to the interfacial resonance states induced by the B diffusion into MgO spacer.

• OSTI ID: 22594644
• Journal Information: Journal of Applied Physics, Journal Name: Journal of Applied Physics Journal Issue: 16 Vol. 119; ISSN JAPIAU; ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ASYMMETRY
ATOMS
BORON
DIAGRAMS
DIFFUSION
DOPED MATERIALS
ENERGY LEVELS
MAGNESIUM
MAGNESIUM OXIDES
MAGNETIC TUNNEL JUNCTIONS
RESONANCE
SPIN
SYMMETRY
TORQUE
WAVE FUNCTIONS