Impact of Cr doping on Hall resistivity and magnetic anisotropy in SrRuO₃ thin films

Hall effects, including anomalous and topological types, in correlated ferromagnetic oxides provide an intriguing framework to investigate emergent phenomena arising from the interaction between spin-orbit coupling and magnetic fields. SrRuO₃is a widely studied itinerant ferromagnetic system with intriguing electronic and magnetic characteristics. The electronic transport of SrRuO₃is highly susceptible to the defects (O/Ru vacancy, chemical doping, ion implantation), and interfacial strain. In this regard, we investigate the impact of Cr doping on the magnetic anisotropy and the Hall effect in SrRuO₃thin films. The work encompasses a comprehensive analysis of the structural, spectroscopic, magnetic, and magnetotransport properties of Cr-doped SrRuO₃films grown on SrTiO₃(001) substrates. Cross-sectional transmission electron microscopy reveals a sharp and coherent interface between the layers. Notably, perpendicular magnetic anisotropy is preserved in doped films with thicknesses up to 113 nm. The resistivity exhibits a<i>T</i>²dependence below the Curie temperature, reflecting the influence of disorder and correlation-induced localization effects. Interestingly, in contrast to the undoped parent compound SrRuO₃, an anomaly in the Hall signal has been observed up to a large thickness (56 nm) attributed to the random Cr doping and Ru vacancy. Based on our measurements, a field-temperature (<i>H</i> - <i>T</i>) phase diagram of anomalous Hall resistivity is constructed.