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We demonstrate a high-throughput experimental characterization of anomalous Nernst conductivity (αxy_A) of L10-ordered CoPt using Co1–xPtx composition-spread thin films on MgO(100) substrates. The compositional dependence of the anomalous Nernst effect (ANE), anomalous Hall effect (AHE) and Seebeck effect is systematically measured. As increasing the Pt concentration, the crystal structure in the composition-spread film grown at 500 °C changes from fcc Co, A1-disordered CoPt, L10-ordered CoPt, A1-CoPt to fcc Pt. The largest αxy_A of 2.52 A m–1 K–1 is obtained in L10-CoPt for Pt-rich composition of x = 70%, which is larger than that for an additionally fabricated nearly stoichiometric L10-Co48Pt52 reference uniform film. The contribution from direct conversion of a temperature gradient to a transverse charge current through αxy_A is dominant to the total anomalous Nernst coefficient compared to the AHE-related contribution. From a scaling analysis of the AHE, the intrinsic contribution is found to be dominant for x = 70%. A theoretical calculation for αxy_A of L10-Co50Pt50 agrees with the experimental αxy_A value for the nearly stoichiometric reference film by considering on-site Coulomb interaction for Co atoms. We also point out the possible electron doping effect by the addition of Pt in L10-CoPt, which could explain the larger αxy_A for the off-stoichiometric Pt-rich composition than that for the nearly stoichiometric one. Our experimental and theoretical results suggest the potential of L10-CoPt with a large αxy_A originating from the intrinsic mechanism for future thermoelectric applications.

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• Creative Commons BY-NC-ND Attribution-NonCommercial-NoDerivs 4.0 International
  

  This is the Accepted Manuscript version of an article accepted for publication in Journal of Physics D: Applied Physics. 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 https://dx.doi.org/10.1088/1361-6463/ad460e

Keyword: anomalous Nernst conductivity, anomalous Nernst effect, L10-ordered alloy, CoPt, anomalous Hall effect, composition-spread films

Date published: 2024-10-11

Publisher: IOP Publishing

Journal:

• JOURNAL OF PHYSICS D-APPLIED PHYSICS (ISSN: 13616463) vol. 57 issue. 40 p. 405001-

Funding:

• Exploratory Research for Advanced Technology JPMJER2201
• Core Research for Evolutional Science and Technology JPMJCR21O1
• Japan Society for the Promotion of Science JP21H01608
• Ministry of Education, Culture, Sports, Science and Technology JPMXP1122715503

Manuscript type: Author's version (Accepted manuscript)

MDR DOI: https://doi.org/10.48505/nims.4794

First published URL: https://doi.org/10.1088/1361-6463/ad460e

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Updated at: 2025-07-16 08:30:38 +0900

Published on MDR: 2025-07-16 08:17:09 +0900