Interface-to-Surface Transition Induced Topological Hall Effect in 2-Dimensional SrRuO 3 Integrated on Silicon

The topological Hall effect (THE), a transport signature emerging from chiral spin textures induced by structural symmetry breaking and the Dzyaloshinskii–Moriya interaction (DMI), represents a rich frontier in condensed matter physics with promising applications in spintronic devices. To enhance the DMI and thereby induce THE in SrRuO 3 (SRO), we introduce a structural-symmetry-breaking strategy that disrupts the Ru–O termination at the rigid substrate interface. This disruption triggers a transition from a rigid epitaxial interface to a freestanding membrane with unsaturated surface bonds, resulting in asymmetric surface terminations (Sr–O on top and Ru–O at the bottom). Unlike its rigid counterpart, which shows no detectable THE, the freestanding SRO exhibits a pronounced THE signal, persisting up to 100 K while preserving high crystallinity and electronic coherence. The ability to generate robust THE in transferable oxide membranes has direct implications for next-generation spintronics, offering compelling prospects for creating low-power magnetic memory and logic devices based on chiral spin textures.