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arXiv · 1112.0834

Chemical Composition Tuning of the Anomalous Hall Effect in Isoelectronic L10 FePd1-xPtx Alloy Films

Abstract

The anomalous Hall effect (AHE) in L10 FePd1-xPtx alloy films is studied both experimentally and theoretically. We find that the intrinsic contribution (?sigma^int_AH) to the AHE can be significantly increased whereas the extrinsic side-jump contribution (sigma^?sj_AH) can be continuously reduced from being slightly larger than sigma^?int_AH in L10 FePd to being much smaller than sigma^?int_AH in L10 FePt, by increasing the Pt composition x. We show that this chemical composition tuning of the intrinsic contribution is afforded by the stronger spin-orbit coupling strength on the Pd/Pt site when the lighter Pd atoms are replaced by the heavier Pt atoms. Our results provide a means of manipulating the competing AHE mechanisms in ferromagnetic alloys for fuller understanding the AHE and also for technological applications of ferromagnetic alloys.

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BibTeXRIS

P. He, L. Ma, Z. Shi, G. Y. Guo, J. -G. Zheng, Y. Xin, S. M. Zhou. 2011-12-05. Chemical Composition Tuning of the Anomalous Hall Effect in Isoelectronic L10 FePd1-xPtx Alloy Films. https://doi.org/10.1103/physrevlett.109.066402

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