Anomalous Hall Effect in Epitaxial Thin Films of the Hexagonal Heusler MnPtGa Noncollinear Hard Magnet

ORAL

Abstract

Magnetic systems exhibiting spin-canted states have garnered much attention recently for their promising rich exotic properties driven by the real-space spin textures and competing magnetic orders. We report here on the magnetic groundtstate and Berry curvature-driven intrinsic anomalous Hall effect (AHE) of hexagonal Heusler MnPtGa epitaxial thin films.

The centrosymmetric MnPtGa films grown by magnetron sputtering on (0001)-Al2O3 crystallize with an out-of-plane c-axis crystal orientation, along which they exhibit preferential perpendicular magnetic anisotropy below their Curie temperature (TC = 263 K). Below a thermally induced spin reorientation transition at 160 K, the magnetic groundtstate, determined by single-crystal neutron diffraction, is found to be a noncollinear spin canted state where the Mn moments tilt 20° away from the c-axis [1].

Furthermore, the anomalous Hall conductivity (AHC) of MnPtGa epitaxial films is found to exhibit a strongly nonmonotonic behaviour as a function of temperature, whereby the AHC changes sign at T* = 110 K; for all investigated films’ thicknesses (20-60 nm). This hints at a common – intrinsic – mechanism governing both the sign of the AHC and the magnitude of the AHE. Our findings, supported by first-principle calculations, strongly suggest an anomalous Hall effect of intrinsic origin, driven by a momentum-space Berry curvature mechanism [2].

[1] R. Ibarra, E. Lesne et al., Appl. Phys. Lett. 120, 172403 (2022). [2] Adv. Mater. Interfaces (accepted).

*This work was supported by the Deutsche Forschungsgemeinschaft (DFG) under SPP 2137 (project no. 403502666) and the European Union’s Horizon 2020 research and innovation programme under FET-Proactive grant agreement no. 824123 – “Skyrmion-Topological Insulator and Weyl Semimetal Technology” (SKYTOP). We acknowledge the support from the DFG via Projects B05 and C03 of the Collaborative Research Center SFB 1143 (Project-id 247310070) at TU Dresden and from the Würzburg-Dresden Cluster of Excellence on Complexity and Topology in Quantum Matter – ct.qmat (EXC 2147, Project-id 390858490). J.G acknowledges support from the Max Planck Society through the Max Planck Partner Group Programme. The neutron diffraction experiment at D10 was conducted under proposal #5-54-366.

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Publication: Rebeca Ibarra, Edouard Lesne et al., Appl. Phys. Lett. 120, 172403 (2022)
Rebeca Ibarra, Edouard Lesne et al., Adv. Mater. Interfaces (accepted).

Presenters

  • Edouard Lesne

    • Max Planck Institute for Chemical Physics of Solids

Authors

  • Edouard Lesne

    • Max Planck Institute for Chemical Physics of Solids

  • Rebeca Ibarra

    • Max Planck Institute for Chemical Physics of Solids

  • Bushra Sabir

    • University of South Florida, Tampa

  • Bachir Ouladiaff

    • Institut Laue-Langevin,Grenoble, France

  • Ketty Beauvois

    • Institut Laue-Langevin, Grenoble, France

  • Alexandr S Sukhanov

    • Institut für Festkörper- und Materialphysik, Technische Universität Dresden

  • Rafal Wawrzynczak

    • Max Planck Institute for Chemical Physics of Solids
    • MPI CPfS

  • Walter Schnelle

    • Max-Planck-Institute for Plasma Physics
    • Max Planck Institute for Chemical Physics of Solids

  • Anton Devishvili

    • Institut Laue-Langevin, Grenoble, France

  • Dmytro S Inosov

    • 2 Institut für Festkörper- und Materialphysik, Technische Universität Dresden

  • Jacob Gayles

    • University of South Florida
    • University of South Florida, Tampa

  • Claudia Felser

    • Max Planck Institute for Chemical Physic
    • Max Planck Institute for Chemical Physics of Solids

  • Anastasios Markou

    • Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Straße 40, Dresden, 01187, Germany
    • Max Planck Institute for Chemical Physics of Solids