Understanding the role of microstructure in spin-charge conversion efficiency across heavy metal/ferromagnet bilayers

The heavy metal (HM)|ferromagnetic metal (FM) bilayer is a prototypical, all-metallic spintronicheterostructure which easily generates and detects spin. Spin-charge conversion in such layersunderpins proposed spintronic devices and sensors as a method to detect and control theorientation of a magnetisation. However, quantifying the fundamental parameters which dictate theefficiency limits of such devices has been an exacting challenge. In our recent work we haveprobed the role microstructure plays on determining spin scattering at the nanoscale. However,there is lack of consensus in the literature as to whether bulk or surface spin-charge conversiondominates this system. We propose using PNR experiments to determine the precise chemicaland magnetic structure at the Pt/CoFeB interface and compare to our already obtained data, inorder to clarify this situation.