Perpendicular magnetization of Co2FeAl full-Heusler alloy films induced by Pt insertion

Abstract

The perpendicular magnetization of Co2FeAl (CFA) full-Heusler alloy films was achieved by intentional insertion of metal layer Pt into Co2FeAl thin film to induce the interfacial perpendicular magnetic anisotropy (PMA). Experimental results indicate that 0.8 nm Pt insertion can greatly improve the ratio of Hc(out-of-plane)/Hc(in-plane), indicating the generation of PMA in the Pt inserted Co2FeAl thin film. At the same time, the effective damping constant of the Co2FeAl film with 0.8 nm Pt insertion layer is 0.0007, which is low enough for spintronic application. Theoretically, based on the first-principles, total energy calculations also prove that the 0.8 nm Pt insertion into Co2FeAl film can generate the PMA and agrees with the experimental results very well. This work reveals that 0.8 nm Pt layer insertion in Co2FeAl film might pave a way towards possessing both strong PMA and 100% theoretical spin polarization in Heusler alloy films.