Inversion of angular-dependent planar magnetoresistance in epitaxial Pt/γ′-Fe4N bilayers

The conversion between charge and spin through spin-orbit coupling (SOC) is critical in heavy nonmagnetic metal/ferromagnetic metal systems. Here, both the single gamma ' -Fe4N films and the epitaxial Pt/gamma ' -Fe4N bilayers were fabricated by facing-target sputtering. In the Pt(3nm)/gamma ' -Fe4N(t(Fe4N) <= 6nm) bilayers, the anisotropy magnetoresistance (AMR) exhibits an M shape, which is opposite to that of the single gamma ' -Fe4N film with a W shape. Meanwhile, the planar Hall resistivity (PHR) reversal also appears. The inversion of AMR and PHR after capping a 3-nm-thick Pt layer on the gamma ' -Fe4N layer is mainly determined by the interfacial effect, in which the magnetic-proximity-effect induced the interface Pt local moments and the inverse-spin-Hall-effect caused the reflected spin-current to charge-current conversion. Our work helps to understand the interfacial SOC effects and has potential application in the field of magnetic sensors.

Automated summary

The study reveals that the inversion of anisotropy magnetoresistance and planar Hall resistivity by capping a Pt layer on the γ'-Fe4N layer is mainly determined by the interfacial effect, shedding light on the interfacial SOC effects and potential applications in magnetic sensors.