Tunneling magnetoresistance in Fe{sub 3}Si/MgO/Fe{sub 3}Si(001) magnetic tunnel junctions

Journal Article · Mon Apr 28 04:00:00 EDT 2014 · Applied Physics Letters

DOI:https://doi.org/10.1063/1.4874837· OSTI ID:22267728

Tao, L. L.; Liang, S. H.; Liu, D. P.; Wei, H. X.; Wang, Jian ^[1]

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1. Department of Physics and the Center of Theoretical and Computational Physics, The University of Hong Kong, Hong Kong (China)

We present a theoretical study of the tunneling magnetoresistance (TMR) and spin-polarized transport in Fe{sub 3}Si/MgO/Fe{sub 3}Si(001) magnetic tunnel junction (MTJ). It is found that the spin-polarized conductance and bias-dependent TMR ratios are rather sensitive to the structure of Fe{sub 3}Si electrode. From the symmetry analysis of the band structures, we found that there is no spin-polarized Δ{sub 1} symmetry bands crossing the Fermi level for the cubic Fe{sub 3}Si. In contrast, the tetragonal Fe{sub 3}Si driven by in-plane strain reveals half-metal nature in terms of Δ{sub 1} state. The giant TMR ratios are predicted for both MTJs with cubic and tetragonal Fe{sub 3}Si electrodes under zero bias. However, the giant TMR ratio resulting from interface resonant transmission for the former decreases rapidly with the bias. For the latter, the giant TMR ratio can maintain up to larger bias due to coherent transmission through the majority-spin Δ{sub 1} channel.

• OSTI ID: 22267728
• Journal Information: Applied Physics Letters, Journal Name: Applied Physics Letters Journal Issue: 17 Vol. 104; ISSN APPLAB; ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
FERMI LEVEL
IRON SILICIDES
MAGNESIUM OXIDES
MAGNETORESISTANCE
SPIN ORIENTATION
SUPERCONDUCTING JUNCTIONS
TUNNEL EFFECT