Two-dimensional electron gases (2DEGs) at perovskite oxide interfaces, such as strontium titanate (STO), have garnered significant attention due to their induced ferromagnetic (FM), spin–orbit coupling, and superconducting properties. The , formed at the interface between STO and either insulating oxides or reactive metals, exhibits efficient charge-to-spin interconversion in (non-magnetic) structures. The insulating oxide layer at the interface attenuates the spin currents injected into the ferromagnet. In contrast, the metallic layers facilitate efficient spin current injection but suffer from spin current diffusion. Here, we present an approach to overcome these challenges by directly creating a at the surface through ion bombardment. This method enables efficient spin-to-charge conversion without an intermediate NM layer. Our experimental and simulation results demonstrate the generation of unconventional spin currents at the interface. Our findings may enable applications of complex oxide and ferromagnet interfaces for efficient charge-to-spin conversion, paving the way for low-power, room-temperature oxide-based spintronic devices.
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