The effect of the rare-earth (RE) metals (La and Yb) intercalation on the electronic and magnetic properties of the graphene/Ni(111) interface is studied using state-of-the-art density functional theory calculations. In both systems, the intercalation of RE leads to the dramatic decrease of the magnetic moments of the Ni-interface atoms and to the negligible moments of C-atoms in a graphene layer, compared to the parent graphene/Ni(111) system. At the same time, the significant n$n$-doping of graphene together with a band-gap opening is observed in both cases of the RE intercalation with a position of the graphene Dirac point reaching ED−EF≈−1.53$E_{\mathrm{D}}-E_{\mathrm{F}}\approx -1.53$ eV. Also the large density of states is found in the vicinity of the Fermi level (EF$E_{\mathrm{F}}$) along the M−K$M-K$ direction for the graphene-derived π$\pi$ states which can be attributed to the joint effect of the intercalated RE and interface Ni atoms. These factors – increased density of states at EF$E_{\mathrm{F}}$ and absence of magnetism of C-atoms in a graphene layer – indicate the possibility of the observation of the superconductive state in graphene in the considered RE-based systems, which is important for the understanding of these and other electronics effects in the graphene-based systems.

中文翻译：

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石墨烯/RE/Ni(111) (RE: La, Yb) 类插层界面的电子和磁性特性：DFT 分析

使用最先进的密度泛函理论计算研究了稀土 (RE) 金属 (La 和 Yb) 插层对石墨烯/Ni(111) 界面的电子和磁性的影响。在这两个系统中，与母体石墨烯/Ni(111) 系统相比，RE 的嵌入导致 Ni 界面原子的磁矩显着降低，并且石墨烯层中 C 原子的磁矩可以忽略不计。同时，显着n$n$-在稀土嵌入的两种情况下都观察到石墨烯的掺杂和带隙开口，石墨烯狄拉克点的位置达到乙D-乙F≈ − 1.53$E_{\mathrm{D}}-E_{\mathrm{F}}\approx -1.53$ eV。在费米能级附近也发现了大的态密度（乙F$E_{\mathrm{F}}$） 沿着米- K$M-K$石墨烯衍生的方向π$\pi$状态可归因于插入的 RE 和界面 Ni 原子的联合效应。这些因素——在乙F$E_{\mathrm{F}}$并且石墨烯层中没有 C 原子的磁性——表明在所考虑的基于 RE 的系统中观察石墨烯中的超导状态的可能性，这对于理解基于石墨烯的这些和其他电子效应很重要系统。