Interfacial mechanism in the anomalous Hall effect of Co/Bi2O3 bilayers

Oxide interfaces are a source of spin-orbit coupling which can lead to novel spin-to-charge conversion effects. In this Rapid Communication, the contribution of the $\mathrm{B}{\mathrm{i}}_{2}{\mathrm{O}}_{3}$ interface to the anomalous Hall effect (AHE) of Co is experimentally studied in $\mathrm{Co}/\mathrm{B}{\mathrm{i}}_{2}{\mathrm{O}}_{3}$ bilayers. We evidence a variation of \ensuremath{\sim}40% in the AHE of Co when a $\mathrm{B}{\mathrm{i}}_{2}{\mathrm{O}}_{3}$ capping layer is added to the ferromagnet. This strong variation is attributed to an additional source of asymmetric transport in $\mathrm{Co}/\mathrm{B}{\mathrm{i}}_{2}{\mathrm{O}}_{3}$ bilayers that originates from the $\mathrm{Co}/\mathrm{B}{\mathrm{i}}_{2}{\mathrm{O}}_{3}$ interface and contributes to the skew scattering.