PNR determination of magnetic interface states in ultrathin FePt/FeRh films

We propose to use polarized neutron reflectivity (PNR) to investigate the structural and magnetic properties of thin (< 10nm) exchange coupled FePt/FeRh films. FePt/FeRh is an artificial multifunctional material that responses to both heat and magnetic fields due to the antiferromagnetic to ferromagnetic phase transition that occurs in FeRh at around 100°C. Exchange coupled FePt/FeRh films are of particular interest as data storage media for heat assisted magnetic recording (HAMR) as they offer the potential to reduce the heat load need for recording which is a key industry challenge. Our objective in this experiment is to investigate the interplay and exchange coupling between the FeRh and FePt layers vs temperature and hence undercover the rich physics that occurs at the interface between these two materials which is key to developing future applications.