Spin-diversified quasiparticle behaviors in rare-rare-earth La- and Eu-adsorbed germanene materials

In this chapter, the rare-earth adatom adsorption on a 2D germanene exhibit a diverse and unique chemical property. The significant hybridization of the RE and Ge atoms leading to the enhanced of the bulked height, and thus, lead to distort of the π-bondings. The rich and diverse electronic properties include n-type doping behaviors with the significantly blue-shift of the Fermi level, the electron transfers are gradually changing with kinds and adatoms concentrations, the dominated & co-dominated of RE and Ge atoms in the conductions and valence bands, the active orbital-hybridizations-related to the orbital hybridizations. The Eu-adsorbed germanene exhibits the ferromagnetic ordered, which clearly reflects on the slitting of spin-up/spin-down states on the energy band structures, the polarized density of states and the spin density distributions. In addition, the optical excitations of germanene are also changed under RE-chemisorption, the main feature cover the unique single-particle excitations, the plasmon modes - collective excitations of charges in term of energy loss functions, absorption, reflection spectrums.