  The interface composed of magnets and strong spin-orbit coupling (SOC)
materials forms an important platform for spintronic devices and intriguing
magnetic phenomena, such as the chiral spin textures and magnetic proximity
effect (MPE). The interface exchange interaction and Dzyaloshinskii-Moriya
interaction (DMI) have been discussed in a wide range of heterostructures,
while the crystal stacking geometry modulation on these interface interactions
has rarely been considered. Here, we show a pronounced geometry modulation on
the interface magnetism through comparing a rutile and an anatase IrO2 capping
on a ferrimagnetic CoFe2O4. The rutile heterostructure with a high-symmetry
interface shows a conventional anomalous Hall effect (AHE) profile due to the
MPE. In contrast, the anatase one with a low-symmetry interface exhibits a
topological-like AHE even at zero-field, suggesting the emergence of
non-coplanar magnetic order at the interface. Our results suggest that the
influence of DMI at the interface can be more accentuated by forming a
low-symmetry interface and raises a new means of designing interface magnetism
via the geometry modulation.
