Skew scattering dominated anomalous Hall effect in Cox(MgO)100-x granular thin films

Handle URI:
http://hdl.handle.net/10754/625302
Title:
Skew scattering dominated anomalous Hall effect in Co<i><sub>x</sub></i>(MgO)<sub>100-<i>x</i></sub> granular thin films
Authors:
Zhang, Qiang; Wen, Yan; Zhao, Yuelei; Li, Peng ( 0000-0001-8633-9045 ) ; He, Xin ( 0000-0001-7009-2826 ) ; Zhang, Junli; He, Yao; Peng, Yong; Yu, Ronghai; Zhang, Xixiang ( 0000-0002-3478-6414 )
Abstract:
We investigated the mechanism(s) of the anomalous Hall effect (AHE) in magnetic granular materials by fabricating 100-nm-thick thin films of Co<i><sub>x</sub></i>(MgO)<sub>100-<i>x</i></sub> with a Co volume fraction of 34≤<i>x</i>≤100 using co-sputtering at room temperature. We measured the temperature dependence of longitudinal resistivity (<i>ρ<sub>xx</sub></i>) and anomalous Hall resistivity (<i>ρ</i><sub>AHE</sub>) from 5 K to 300 K in all samples. We found that when <i>x</i> decreases from 100 to 34, the values of <i>ρ<sub>xx</sub></i> and <i>ρ</i><sub>AHE</sub> respectively increased by about four and three orders in magnitude. By linearly fitting the data, obtained at 5 K, of anomalous Hall coefficient (<i>R<sub>s</sub></i>) and of <i>ρ<sub>xx</sub></i> to log(<i>R<sub>s</sub></i>)~<i>γ</i>log(<i>ρ<sub>xx</sub></i>), we found that our results perfectly fell on a straight line with a slope of <i>γ</i>= 0.97±0.02. This fitting value of <i>γ</i> in <i>R<sub>s</sub></i>∝<i>ρ<sub>xx</sub></i><i><sup>γ</sup></i> clearly suggests that skew scattering dominated the AHE in this granular system. To explore the effect of the scattering on the AHE, we performed the same measurements on annealed samples. We found that although both <i>ρ<sub>xx</sub></i> and <i>ρ</i><sub>AHE</sub> significantly reduced after annealing, the correlation between them was almost the same, which was confirmed by the fitted value, <i>γ</i>=0.99±0.03. These data strongly suggest that the AHE originates from the skew scattering in Co-MgO granular thin films no matter how strong the scatterings of electrons by the interfaces and defects is. This observation may be of importance to the development of spintronic devices based on MgO.
KAUST Department:
Physical Sciences and Engineering (PSE) Division; Imaging and Characterization Core Lab
Citation:
Zhang Q, Wen Y, Zhao Y, Li P, He X, et al. (2017) Skew scattering dominated anomalous Hall effect in Cox(MgO)100-x granular thin films. Journal of Physics: Condensed Matter. Available: http://dx.doi.org/10.1088/1361-648x/aa8315.
Publisher:
IOP Publishing
Journal:
Journal of Physics: Condensed Matter
Issue Date:
31-Jul-2017
DOI:
10.1088/1361-648x/aa8315
Type:
Article
ISSN:
0953-8984; 1361-648X
Sponsors:
The research reported in this publication was supported by funding from King Abdullah University of Science and Technology (KAUST). QZ and PL acknowledge financial support from KAUST sensor project (REP/1/2708-01). XH acknowledges financial support from KAUST sensor project (REP/1/2719-01).
Additional Links:
http://iopscience.iop.org/article/10.1088/1361-648X/aa8315
Appears in Collections:
Articles; Advanced Nanofabrication, Imaging and Characterization Core Lab; Physical Sciences and Engineering (PSE) Division

Full metadata record

DC FieldValue Language
dc.contributor.authorZhang, Qiangen
dc.contributor.authorWen, Yanen
dc.contributor.authorZhao, Yueleien
dc.contributor.authorLi, Pengen
dc.contributor.authorHe, Xinen
dc.contributor.authorZhang, Junlien
dc.contributor.authorHe, Yaoen
dc.contributor.authorPeng, Yongen
dc.contributor.authorYu, Ronghaien
dc.contributor.authorZhang, Xixiangen
dc.date.accessioned2017-08-07T10:52:01Z-
dc.date.available2017-08-07T10:52:01Z-
dc.date.issued2017-07-31en
dc.identifier.citationZhang Q, Wen Y, Zhao Y, Li P, He X, et al. (2017) Skew scattering dominated anomalous Hall effect in Cox(MgO)100-x granular thin films. Journal of Physics: Condensed Matter. Available: http://dx.doi.org/10.1088/1361-648x/aa8315.en
dc.identifier.issn0953-8984en
dc.identifier.issn1361-648Xen
dc.identifier.doi10.1088/1361-648x/aa8315en
dc.identifier.urihttp://hdl.handle.net/10754/625302-
dc.description.abstractWe investigated the mechanism(s) of the anomalous Hall effect (AHE) in magnetic granular materials by fabricating 100-nm-thick thin films of Co<i><sub>x</sub></i>(MgO)<sub>100-<i>x</i></sub> with a Co volume fraction of 34≤<i>x</i>≤100 using co-sputtering at room temperature. We measured the temperature dependence of longitudinal resistivity (<i>ρ<sub>xx</sub></i>) and anomalous Hall resistivity (<i>ρ</i><sub>AHE</sub>) from 5 K to 300 K in all samples. We found that when <i>x</i> decreases from 100 to 34, the values of <i>ρ<sub>xx</sub></i> and <i>ρ</i><sub>AHE</sub> respectively increased by about four and three orders in magnitude. By linearly fitting the data, obtained at 5 K, of anomalous Hall coefficient (<i>R<sub>s</sub></i>) and of <i>ρ<sub>xx</sub></i> to log(<i>R<sub>s</sub></i>)~<i>γ</i>log(<i>ρ<sub>xx</sub></i>), we found that our results perfectly fell on a straight line with a slope of <i>γ</i>= 0.97±0.02. This fitting value of <i>γ</i> in <i>R<sub>s</sub></i>∝<i>ρ<sub>xx</sub></i><i><sup>γ</sup></i> clearly suggests that skew scattering dominated the AHE in this granular system. To explore the effect of the scattering on the AHE, we performed the same measurements on annealed samples. We found that although both <i>ρ<sub>xx</sub></i> and <i>ρ</i><sub>AHE</sub> significantly reduced after annealing, the correlation between them was almost the same, which was confirmed by the fitted value, <i>γ</i>=0.99±0.03. These data strongly suggest that the AHE originates from the skew scattering in Co-MgO granular thin films no matter how strong the scatterings of electrons by the interfaces and defects is. This observation may be of importance to the development of spintronic devices based on MgO.en
dc.description.sponsorshipThe research reported in this publication was supported by funding from King Abdullah University of Science and Technology (KAUST). QZ and PL acknowledge financial support from KAUST sensor project (REP/1/2708-01). XH acknowledges financial support from KAUST sensor project (REP/1/2719-01).en
dc.publisherIOP Publishingen
dc.relation.urlhttp://iopscience.iop.org/article/10.1088/1361-648X/aa8315en
dc.rightsThis is an author-created, un-copyedited version of an article accepted for publication/published in Journal of Physics: Condensed Matter. IOP Publishing Ltd is not responsible for any errors or omissions in this version of the manuscript or any version derived from it. The Version of Record is available online at http://doi.org/10.1088/1361-648x/aa8315en
dc.titleSkew scattering dominated anomalous Hall effect in Co<i><sub>x</sub></i>(MgO)<sub>100-<i>x</i></sub> granular thin filmsen
dc.typeArticleen
dc.contributor.departmentPhysical Sciences and Engineering (PSE) Divisionen
dc.contributor.departmentImaging and Characterization Core Laben
dc.identifier.journalJournal of Physics: Condensed Matteren
dc.eprint.versionPost-printen
dc.contributor.institutionKey Laboratory for Magnetism and Magnetic Materials of the Ministry of Education, Lanzhou University, Lanzhou 730000, Gansu, Lanzhou, CHINA.en
dc.contributor.institutionBeihang University, beijing, CHINA.en
kaust.authorZhang, Qiangen
kaust.authorWen, Yanen
kaust.authorZhao, Yueleien
kaust.authorLi, Pengen
kaust.authorHe, Xinen
kaust.authorZhang, Junlien
kaust.authorHe, Yaoen
kaust.authorZhang, Xixiangen
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