论文标题
在应变下，最小扭曲的双层石墨烯中域壁网络的能量和结构
Energetics and Structure of Domain Wall Networks in Minimally Twisted Bilayer Graphene under Strain
论文作者
论文摘要
使用两链Frenkel-Kontorova模型研究了双层石墨烯中三角形域壁网络的参数。证明，如果石墨烯层可以自由旋转，则希望在拉伸底层时保持对齐，并且在相应量合规的相变的张力域壁上形成了拉伸域壁的常规三角网络。如果两层之间的角度固定，则在底层的零伸长率下观察到剪切结构域壁的常规三角网络。然而，在拉伸底层后，域壁转变为拉伸的壁，相应域的大小减小。我们还表明，在剪切应变下，在扭曲的双层石墨烯中，同步三角形域壁网络的参数可以通过纯粹的几何考虑来确定。一方面，对域壁的方向和三角网络的周期的实验分析将有助于理解石墨烯层的层间相互作用，另一方面，有助于检测层之间的相对应变和旋转。副外应变可用于控制三角形域壁网络的参数，因此可以使用扭曲的双层石墨烯的电子性质。
The parameters of the triangular domain wall network in bilayer graphene with a simultaneously twisted and biaxially stretched bottom layer are studied using the two-chain Frenkel-Kontorova model. It is demonstrated that if the graphene layers are free to rotate, they prefer to stay co-aligned upon stretching the bottom layer and the regular triangular network of tensile domain walls is formed upon the commensurate-incommensurate phase transition. If the angle between the layers is fixed, the regular triangular network of shear domain walls is observed at zero elongation of the bottom layer. Upon stretching the bottom layer, however, the domain walls transform into the tensile ones and the size of the commensurate domains decreases. We also show that the parameters of the isosceles triangular domain wall network in twisted bilayer graphene under shear strain can be determined through purely geometrical considerations. Experimental analysis of the orientation of domain walls and period of the triangular network would, on the one hand, contribute to understanding of the interlayer interaction of graphene layers, and, on the other hand, serve for detection of relative strains and rotation between the layers. Vice versa external strains can be used to control the parameters of the triangular domain wall network and, therefore, electronic properties of twisted bilayer graphene.
