论文标题
在圆极化的光照射下，石墨烯在HBN上增强的谷地极化
Enhanced valley polarization of graphene on hBN under circularly polarized light irradiation
论文作者
论文摘要
HBN上的石墨烯（G/HBN）具有长时间的Moiré上部结构，这是由于两种材料之间的晶格不匹配。由Moiré上层建筑引起的长期周期电势会导致系统的电子性质调制。在本文中，我们通过数值计算圆形极化光照射下的G/HBN的光导率。 G/HBN中缺乏空间反演对称性会导致山谷极化。此外，如果两种材料之间的扭角接近零，则在红外和Terahertz区域中，山谷极化最为明显，但是，对于孔掺杂的情况而言，对扭曲角度不敏感。这些结果将有助于使用G/HBN设计ValleyTronics设备。
Graphene on hBN (G/hBN) has a long period moiré superstructure owing to the lattice mismatch between two materials. Long periodic potential caused by the moiré superstructure induces modulation of electronic properties of the system. In this paper, we numerically calculate optical conductivity of G/hBN under circularly polarized light irradiation. The lack of spatial inversion symmetry in G/hBN induces the valley polarization. In further, the valley polarization becomes most pronounced in the infrared and terahertz regions if the twist angle between two materials is close to zero for non-doping case, however, insensitive with twist angle for hole-doped case. These results will serve to design the valleytronics devices using G/hBN.
