Metastable SrRuO3 phases with lattice-dependent magnetic anisotropy by tailoring interfacial oxygen octahedral coupling

Tunable magnetic anisotropy can greatly facilitate the integration of perovskite oxides in emerging magnetic memory devices. Tailoring the metastable structures is a powerful and effective method to tune the magnetic anisotropy of perovskite oxides possessing a large spin-lattice correlation. Herein, we stabilized SrRuO3 (SRO) at two metastable phases by tailoring the interfacial octahedral coupling between SRO and LaCoO3 (LCO). Two metastable phases, distorted-rhombohedral and tetragonal structures, were stabilized in turn as the SRO thickness increased. Through the stabilization of these metastable phases, we realized a strongly lattice-dependent magnetic anisotropy and magnetic structure symmetry of SRO, employing its large spin-orbit coupling. Detailed octahedral rotation analysis demonstrated that when the SRO film was thin, the rotation phase mismatch between SRO and LCO played a decisive role in stabilizing the distorted-rhombohedral phase, while the competition between the rotation phase mismatch and tilt propagation relaxation induced the tetragonal phase when the SRO film was thick. These results demonstrate the feasibility of tailoring various structural symmetries and exotic functionalities through interface coupling.

Automated summary

In this study, the stabilization of SrRuO3 in two metastable phases through interface coupling was achieved, enabling the tunability of magnetic anisotropy in perovskite oxides and revealing the large spin-lattice correlation. The results demonstrate the feasibility of tailoring the structural symmetry and functionality of perovskite oxides through interface coupling.