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Influence of Roughness and Disorder on Tunneling Magnetoresistance

P. X. Xu·V. M. Karpan·K. Xia·M. Zwierzycki·I. Marushchenko·P. J. Kelly
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Abstract

A systematic, quantitative study of the effect of interface roughness and disorder on the magnetoresistance of FeCo$|$vacuum$|$FeCo magnetic tunnel junctions is presented based upon parameter-free electronic structure calculations. Surface roughness is found to have a very strong effect on the spin-polarized transport while that of disorder in the leads (leads consisting of a substitutional alloy) is weaker but still sufficient to suppress the huge tunneling magneto-resistance (TMR) predicted for ideal systems.

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P. X. Xu, V. M. Karpan, K. Xia, M. Zwierzycki, I. Marushchenko, P. J. Kelly. 2006-05-30. Influence of Roughness and Disorder on Tunneling Magnetoresistance. https://doi.org/10.1103/physrevb.73.180402

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