Suppression of the Cycloidal Spin Arrangement in BiFeO3 Caused by the Mechanically Induced Structural Distortion and Its Effect on Magnetism

Frontiers in Materials

Rodolfo Bezerra Da Silva¹  Rafael Santiago Trautwein²  Marta Harničárová⁴  Vladimír Šepelák⁴  Dirk Menzel⁵  Klebson Lucenildo Da Silva⁶  Olha Skurikhina⁶  Martin Fabián⁶  Horst Hahn⁷  Klaus Dieter Becker⁸  Mariia Holub⁹  Erik Čižmár⁹  Vladimír Girman⁹ 

[1] Department of Physics, Federal University of Rio Grande do Norte, Natal, Brazil;Department of Physics, State University of Maringá, Maringá, Brazil;Faculty of Engineering, Slovak University of Agriculture, Nitra, Slovakia;Faculty of Technology, College of Technology and Business in České Budějovice, České Budějovice, Czech Republic;Institute of Condensed Matter Physics, Braunschweig University of Technology, Braunschweig, Germany;Institute of Geotechnics, Slovak Academy of Sciences, Košice, Slovakia;Institute of Nanotechnology, Karlsruhe Institute of Technology, Eggenstein-Leopoldshafen, Germany;Institute of Physical and Theoretical Chemistry, Braunschweig University of Technology, Braunschweig, Germany;Institute of Physics, Faculty of Science, P. J. Šafárik University, Košice, Slovakia;

关键词: multiferroic;    bismuth ferrite;    cycloidal spin arrangement;    mechanochemistry;    Mössbauer spectroscopy;   

DOI  :  10.3389/fmats.2021.717185

来源: DOAJ

【 摘 要 】

Bismuth ferrite (BiFeO3) particles are prepared by a combined mechanochemical−thermal processing of a Bi2O3 + α-Fe2O3 mixture. Structural, magnetic, hyperfine, morphological and chemical properties of the as-prepared BiFeO3 are studied using X-ray diffraction (Rietveld refinement), 57Fe Mössbauer spectroscopy, SQUID magnetometry, electron microscopy and energy dispersive X-ray spectroscopy. It is revealed that the structure of the ferrite exhibits the long-range distortion (significantly tilted FeO6 octahedra) and the short-range disorder (deformed FeO6 octahedra). Consequently, these structural features result in the suppression of a space modulated cycloidal spin arrangement in the material. The latter manifests itself by the appearance of only single spectral component in the 57Fe Mössbauer spectrum of BiFeO3. The macroscopic magnetic behavior of the material is interpreted as a superposition of ferromagnetic and antiferromagnetic contributions with a large coercive field and remanent magnetization. Taking into account the average particle size of the as-prepared BiFeO3 particles (∼98 nm), exceeding the typical period length of cycloid (∼62 nm), both the suppression of the spiral spin structure in the material and its partly ferromagnetic behavior are attributed to the crystal lattice distortion caused by mechanical stress during the preparation procedure.

【 授权许可】

Unknown