First-principles study of van der Waals heterostructure of 2D material and iron-based ferromagnetic alloy

This work investigates the first-principle analysis of the van der Waals hetero interface between the 2D materials and ferromagnetic alloys such as FePd and FeNi. The FePd alloy is characterized by its L10-ordered structure and is focused on the spintronics materials owing to its large magnetic anisotropy and small Gilbert damping. Recent experimental advancements have enabled the synthesis of heterointerfaces between FePd and graphene. We have theoretically predicted the interface's atomic structure alongside its electronic and magnetic properties. In our previous works, we have performed first-principles spin transport calculations, which indicate magnetoresistance ratio reaches 100% ~ 300% in the FePd/Gr/FePd heterojunction. In addition, we have extended our investigation to the interfaces of various other 2D materials, including hBN, PdSe2, and WS2. We have also considered another ferromagnetic alloy, FeNi. In the case of FeNi/Gr, our calculation result reveals that Fe-rich atomic layers are more stable at the interface, which is different from that of bulk alloy. Such atomic scale behavior mainly reflects Fe(3d) and C(2p) hybridized states. This work aims to contribute to the understanding of integrating 2D materials with ferromagnetic alloys for advanced spintronic applications.