Effect of surface roughness on the anomalous Hall effect in Fe thin films

Abstract

Surface roughness plays an important role on the magnetotransport properties of thin films, especially in ultrathin films. In this work, we prepared Fe thin films with various surface roughness by using different seed layers and studied the electrical transport and anomalous Hall effect. By tuning surface roughness scattering, the longitudinal resistivity (${\ensuremath{\rho}}_{xx}$) measured at 5 K increases by one order of magnitude and the corresponding anomalous Hall resistivity (${\ensuremath{\rho}}_{\mathrm{AHE}}$) increases by three times with increasing roughness. The intrinsic, skew-scattering, and side-jump contributions to ${\ensuremath{\rho}}_{\mathrm{AHE}}$ were separated from our data. The anomalous Hall angle depends on the surface roughness, which may be of importance to the material engineering for achieving large spin Hall angle.