Artificial fabrication and characterization of L1<inf>0</inf>-ordered FeNi thin films

Abstract

L1 0 -FeNi, showing uniaxial magnetic anisotropy (K u ) of 1.3×107 erg/cm3 in a bulk sample[1], is promising as a “rare metal-free” high K u material. It is known that iron meteorites contain the L1 0 -FeNi phase, what is called “tetrataenite”, which reveals unique magnetic properties different from usual Fe-Ni alloys[2]. However, the artificial fabrication of L1 0 -FeNi is difficult because the order-disorder transformation temperature is low (∼320C), and below this temperature the atomic diffusion is extremely slow. In this study, we have tried to fabricate L1 0 -FeNi thin films with high K u by two methods: molecular beam epitaxy (MBE) and sputtering.