The effect of interface roughness on proximity induced magnetisation and interface spin transparency in Pt/CoFeB/Cu thin films.

Interface effects, including proximity induced magnetisation (PIM), play an import role in many spintronic devices employing heavy metal/ferromagnetic structures. Interface quality, including roughness and intermixing leads to modifications of interface properties such as the spin transparency. Polarised neutron reflectometry and X-ray resonant magnetic reflectometry will be used to characterise the magnetic profile of CoFeB and the PIM in Pt respectively in Pt/CoFeB interfaces with varying degrees of induced surface roughness. The new OSMOND detector on PolRef allows for increased surface roughness sensitivity making this investigation now possible. Complimentary measurements will be performed investigating changes in interface spin transparency and current induced magnetisation reversal. This work will go towards publication and contribute in part to the author’s EPSRC DTP funded PhD.