Visualization of topological Hall effect in ultra-thin SrRuO₃ thin films

The topological Hall effect (THE), which originates from the non-coplanar spin textures in real space, has attracted much attention over years. Recently, an interface-driven topological Hall effect has been realized in SrRuO₃-SrIrO₃ bilayer systems[1]. By combining a ferromagnetic SrRuO₃ layer and a paramagnetic SrIrO₃ layer with strong spin-orbital coupling, large DM interaction was introduced on the interface, which presumably results in a Neel-type magnetic skyrmion phase with substantial THE. In this talk, we will report the observation of THE in the SrRuO₃ ultrathin films without SrIrO₃ layer using magnetic force microscopy (MFM) with in-situ transport. Possible mechanisms of the THE in these SrRuO₃ ultrathin films will be presented.
[1] J. Matsuno et al., Science Advances, 2, e1600304 (2016)