Continuous tunable lateral magnetic anisotropy in La0.67Ca0.33MnO3/SrRuO3 superlattices by stacking period-modulation

Effective control of magnetic anisotropy is important for developing spintronic devices. In this work, we performed a case study of stacking periods (N)-mediated reorientation of lateral magnetic anisotropy in ultrathin La0.67Ca0.33MnO3/SrRuO3 superlattices. As N increases from 1 to 15, the magnetic easy-axis switches from the orthorhombic [010] to [100]-axis. The maximum anisotropy constant of the superlattice (SL) (N = 15) reaches −1.83 × 105 erg/cm3. X-ray absorption spectroscopy and x-ray linear dichroism further suggest that the observed changes in lateral magnetic anisotropy are driven by in-plane orbital polarization. For SLs with small N, anisotropic strain-induced orbital polarization along the b-axis can result in the [010]-oriented magnetic easy axis. For SLs with large N, the dimension crossover from 2-dimension to 3-dimension could enhance the hybridization of Ru t2g and Mn dx2−y2 orbitals, which can compete with the strain effect and switch the magnetic easy axis to [100]. Our results suggest a potential strategy for engineering magnetic anisotropy through the cooperation of strain engineering and interfacial orbital engineering.