论文标题
SIC上的镁嵌入石墨烯：极端位移场的高度N掺杂空气稳定的双层石墨烯
Magnesium-intercalated graphene on SiC: highly n-doped air-stable bilayer graphene at extreme displacement fields
论文作者
论文摘要
我们使用角度分辨的光发射光谱来研究双层石墨烯在高N兴奋剂和极端位移场上的电子结构，这是通过将碳化硅上的外延单层石墨烯与镁插入镁含镁含镁含有镁的硅硅碳纤维上的二层混合烯。角度分辨光发射光谱表明，在镁插入时，将外延单层石墨烯的单个无质量的泥石带转换为质量融资双层双层石墨烯的特征性质量大型双波段dirac Spectrum。使用简单的紧密结合模型对光谱进行分析表明，镁的插入导致2.1 $ \ times $ 10 $^{14} $^{14} $ cm $^{ - 2} $的N型掺杂，从而产生了一个极高的2.6 v/nm位移场，在Dirac Point of Dirac Point打开了一个相当大的差距为0.36 ev。在镁终止的碳化硅上的准蛋白质双层石墨烯的密度功能理论计算进一步证实了这一点，碳碳酸盐含量相似，该硅碳化物显示出相似的掺杂水平，位移场和带隙。最后，对环境条件的镁缩小样品令人惊讶。空气中30分钟后，没有观察到电子结构的显着变化。
We use angle-resolved photoemission spectroscopy to investigate the electronic structure of bilayer graphene at high n-doping and extreme displacement fields, created by intercalating epitaxial monolayer graphene on silicon carbide with magnesium to form quasi-freestanding bilayer graphene on magnesium-terminated silicon carbide. Angle-resolved photoemission spectroscopy reveals that upon magnesium intercalation, the single massless Dirac band of epitaxial monolayer graphene is transformed into the characteristic massive double-band Dirac spectrum of quasi-freestanding bilayer graphene. Analysis of the spectrum using a simple tight binding model indicates that magnesium intercalation results in an n-type doping of 2.1 $\times$ 10$^{14}$ cm$^{-2}$, creates an extremely high displacement field of 2.6 V/nm, opening a considerable gap of 0.36 eV at the Dirac point. This is further confirmed by density-functional theory calculations for quasi-freestanding bilayer graphene on magnesium-terminated silicon carbide, which show a similar doping level, displacement field and bandgap. Finally, magnesium-intercalated samples are surprisingly robust to ambient conditions; no significant changes in the electronic structure are observed after 30 minutes exposure in air.
