Intermixing of ordinary and anomalous Hall effect inSrRuO3

Abstract

The Hall effect resistivity ${\ensuremath{\rho}}_{xy}$ of high-quality films of the itinerant ferromagnet ${\mathrm{SrRuO}}_{3}$ was measured at low temperatures. ${\mathrm{SrRuO}}_{3}$ films have large uniaxial magnetocrystalline anisotropy, and in the relevant temperature range the easy axis is ${30}^{\ensuremath{\circ}}$ degrees from the film normal. We measure changes in ${\ensuremath{\rho}}_{xy}$ associated with changes in the orientation of the magnetization (M) for the same applied magnetic field B $[\mathrm{\ensuremath{\Delta}}{\ensuremath{\rho}}_{xy}(\mathbf{B},\mathrm{\ensuremath{\Delta}}\mathbf{M})]$, and we find that with increasing B, $\mathrm{\ensuremath{\Delta}}{\ensuremath{\rho}}_{xy}(\mathbf{B},\mathrm{\ensuremath{\Delta}}\mathbf{M})$ changes its sign and its magnitude becomes more than an order of magnitude larger than the remanent (spontaneous) anomalous Hall effect. Furthermore, it appears that ${\ensuremath{\rho}}_{xy}$ cannot be described as a sum of a term that depends on B and a term that depends on M, that is, the ordinary Hall effect and the anomalous Hall effect are effectively intermixed. We address qualitatively a possible link between the observed behavior of ${\ensuremath{\rho}}_{xy}$ and the predicted existence of Weyl nodes in ${\mathrm{SrRuO}}_{3}$.