Fig. 1: Simplified illustration of the 3d states in Ni, Fe19Ni81, and Fe50Ni50.
From: Verification of ultrafast spin transfer effects in iron-nickel alloys
The addition of Fe in the alloys leads to additional unoccupied states in the minority channel that can be populated through optical intersite spin transfer (OISTR). Time-dependent density functional theory calculations predict a stronger OISTR effect in Fe50Ni50 compared to Fe19Ni81 due to the larger amount of available Fe states above the Fermi level35. On the other hand, in elemental Ni, the OISTR process is not possible.
