Dirac-Electron Behavior for Spin-Up Electrons in Strongly Interacting Graphene on Ferromagnetic Mn$_5$Ge$_3$

Abstract

An elegant approach on the synthesis of graphene on the strong ferromagnetic (FM) material Mn$_5$Ge$_3$ is proposed via intercalation of Mn in the graphene-Ge(111) interface. According to the DFT calculations, graphene in this strongly interacting system demonstrates the large exchange splitting of the graphene-derived $\pi$ band. In this case only spin-up electrons in graphene preserve the Dirac-electron-like character in the vicinity of the Fermi level and the K point, whereas such behavior is not detected for the spin-down electrons. This unique feature of the studied gr/FM-Mn$_5$Ge$_3$ interface which can be prepared on the semiconducting Ge can lead to its application in spintronics.