The Hall effect in SrRuO3 thin-films near the thickness limit for
ferromagnetism shows an extra peak in addition to the ordinary and anomalous
Hall effects. This extra peak has been attributed to a topological Hall effect
due to two-dimensional skyrmions in the film around the coercive field;
however, the sign of the anomalous Hall effect in SrRuO3 can change as a
function of saturation magnetization. Here we report Hall peaks in SrRuO3 in
which volumetric magnetometry measurements and magnetic force microscopy
indicate that the peaks result from the superposition of two anomalous Hall
channels with opposite sign. These channels likely form due to thickness
variations in SrRuO3, creating two spatially separated magnetic regions with
different saturation magnetizations and coercive fields. The results are
central to the development of strongly correlated materials for spintronics.This work is supported by the EPSRC through the Core-to-Core International Network “Oxide Superspin” (EP/P026311/1) and the Doctoral Training Partnership Grant (EP/N509620/1). Additional support from the Office of Basic Energy Sciences Division of Materials Sciences and Engineering, US Department of Energy under Award numbers de-sc0018153, and the Research Center Program of IBS (Institute for Basic Science) in Korea (IBS-R009-D1)