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arXiv · 2212.00267

Tuning Structural, Transport and Magnetic Properties of Epitaxial SrRuO3 through Ba-Substitution

Zeeshan Ali·Zhen Wang·Alessandro R. Mazza·Mohammad Saghayezhian·Roshan Nepal·Thomas Z. Ward·Yimei Zhu·Jiandi Zhang
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Abstract

The perovskite ruthenates (ARuO3, A = Ca, Ba, or Sr) exhibit unique properties owing to a subtle interplay of crystal structure and electronic-spin degrees of freedom. Here, we demonstrate an intriguing continuous tuning of crystal symmetry from orthorhombic to tetragonal (no octahedral rotations) phases in epitaxial SrRuO3 achieved via Ba-substitution (Sr1-xBaxRuO3 with 0 < x < 0.7). An initial Ba-substitution to SrRuO3 not only changes the ferromagnetic properties, but also tunes the perpendicular magnetic anisotropy via flattening the Ru-O-Ru bond angle (to 180°), resulting in the maximum Curie temperature and an extinction of RuO6 rotational distortions at x = 0.20. For x > 0.2, the suppression of RuO6 octahedral rotational distortion dominantly enhances the ferromagnetism in the system, though competing with the impact of the RuO6 tetragonal distortion. Further increasing x > 0.2 gradually enhances the tetragonal-type distortion, resulting in the tuning of Ru-4d orbital occupancy and suppression of ferromagnetism. Our results demonstrate that isovalent substitution of the A-site cations significantly and controllably impacts both electronic and magnetic properties of perovskite oxides.

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Zeeshan Ali, Zhen Wang, Alessandro R. Mazza, Mohammad Saghayezhian, Roshan Nepal, Thomas Z. Ward, Yimei Zhu, Jiandi Zhang. 2023-01-28. Tuning Structural, Transport and Magnetic Properties of Epitaxial SrRuO3 through Ba-Substitution. https://doi.org/10.1103/physrevb.107.144405

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