Structural and electronic origin of spin-dependent interface resistance in spintronic Fe/Pt THz emitter by first-principles calculations

Using first-principles methods based on spin density functional theory (SDFT) and multichannel Landauer formalism for spin-transport, we calculated the spin-dependent interface resistance arising from the interface potential barrier due to the shifts in minority (spin-up) and majority (spin-down) conduction bands between Fe and Pt in spintronic Fe/Pt THz emitter. We found that the spin-up interface resistance is lower than that of spin-down in agreement with previous interface reflectivity studies. This direct correlation of spin-transport to structural/electronic properties poses impact on the design of more efficient THz emitters.