First-principle study of spin transport property in \(L1_0\)-FePd(001)/graphene heterojunction

In our previous work, we synthesized a metal/2D material heterointerface consisting of \(L1_0\)-ordered iron-palladium (FePd) and graphene (Gr) called FePd(001)/Gr. This system has been explored by both experimental measurements and theoretical calculations. In this study, we focus on a heterojunction composed of FePd and multilayer graphene referred to as FePd(001)/\(m\)-Gr/FePd(001), where \(m\) represents the number of graphene layers. We perform first-principles calculations to predict their spin-dependent transport properties. The quantitative calculations of spin-resolved conductance and magnetoresistance (MR) ratio (150-200%) suggest that the proposed structure can function as a magnetic tunnel junction in spintronics applications. We also find that an increase in \(m\) not only reduces conductance but also changes transport properties from the tunneling behavior to the graphite \(\pi\)-band-like behavior. Additionally, we investigate the spin-transfer torque-induced magnetization switching behavior of our \color{blue} junction structures \color{black} using micromagnetic simulations. Furthermore, we examine the impact of lateral displacements (``sliding'') at the interface and find that the spin transport properties remain robust despite these changes; this is the advantage of two-dimensional material hetero-interfaces over traditional insulating barrier layers such as MgO.