Spin-filtering effect of thin Al{sub 2}O{sub 3} barrier on tunneling magnetoresistance

Journal Article · Mon Apr 14 04:00:00 EDT 2014 · Applied Physics Letters

DOI:https://doi.org/10.1063/1.4870812· OSTI ID:22262602

Joo, Sungjung ^[1]; Jung, K. Y. ^[2]; Jun, K. I.; Shin, K. H. ^[3]; Kim, D. S.; Hong, J. K.

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1. Center for Electricity and Magnetism, KRISS, Daejeon 305-340 (Korea, Republic of)
2. Department of Display and Semiconductor Physics, Korea University, Sejong 339-700 (Korea, Republic of)
3. Spintronic Device Research Center, KIST, Seoul 136-791 (Korea, Republic of)

Tunneling magnetoresistance (TMR) dependence on the Al{sub 2}O{sub 3} barrier thickness was investigated for CoFe/Al{sub 2}O{sub 3}/CoFe magnetic tunnel junctions (MTJs). MTJs with very thin Al{sub 2}O{sub 3} layers were grown by inserting an amorphous FeZr buffer layer whose role is only to reduce the roughness of bottom electrode. The TMR decreased as the thickness of the Al{sub 2}O{sub 3} layer was reduced. The results are analyzed with the dependence of the spin-filtering effect on the Al{sub 2}O{sub 3} thickness. It was found that a simple model of separating sp- and d-like electrons does not work, and it may suggest that the tunneling electrons are in rather hybridized state.

• OSTI ID: 22262602
• Journal Information: Applied Physics Letters, Journal Name: Applied Physics Letters Journal Issue: 15 Vol. 104; ISSN APPLAB; ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ALUMINIUM OXIDES
MAGNETORESISTANCE
SUPERCONDUCTING JUNCTIONS
TUNNEL EFFECT