Role of competing magnetic anisotropies in deriving topologically nontrivial spin textures in oxide heterostructures

In spatially inverted systems, the complex entanglement of Dzyaloshinskii-Moriya interaction (DMI) and other magnetic anisotropies, mediated by spin-orbit coupling (SOC), influences the emergence and dynamics of the chiral spin textures such as skyrmion. The competing and unified effect of these anisotropies––which is expected to amplify the skyrmionics response in the quantum transport phenomena––is not yet known. Here, we investigate this template and engineer the topological Hall effect (THE) arising from chiral spin texture in a range of $L{a}_{0.7}S{r}_{0.3}\mathrm{Mn}{O}_3/\mathrm{CaIr}{O}_3$ superlattices. The strength of SOC and interfacial DMI are controlled via the architectural design and charge transfer across the interface. All the superlattices display anomalous Hall effect, accompanied by the hump like feature. In ${\left(L_3{I}_y\right)}_4$ ($y=4$, 6, and 8) superlattices, the humplike feature that is deemed as the THE is intrinsic in nature and stems from the chiral spin texture. For the intermediate strength of SOC, unique eightfold anisotropic magnetoresistance oscillations manifest owing to the modulation of the magnetic easy axis in the presence of competing anisotropies. For this superlattice, THE shows remarkable enhancement of the order such that it takes complete precedence over anomalous contribution. The thicker superlattice with higher fraction of charge transfer augments ferromagnetic interactions, and the artificial THE appears as a consequence of a dual-channel anomalous Hall effect. This manipulation of the THE is intricately connected to the concurrent presence of magnetic anisotropies, altering the dynamics of chiral spin texture. These findings expand the understanding of the corroborative contributions of competing anisotropies and yield a comprehensive control of chiral properties––a dimension for the utility in next-generation spintronics technologies.