Abdullah H M, Van Duppen B, Zarenia M, Bahlouli H, Peeters F M
Department of Physics, King Fahd University of Petroleum and Minerals, 31261 Dhahran, Saudi Arabia. Saudi Center for Theoretical Physics, 31261 Dhahran, Saudi Arabia. Department of Physics, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp, Belgium.
J Phys Condens Matter. 2017 Oct 25;29(42):425303. doi: 10.1088/1361-648X/aa81a8. Epub 2017 Jul 24.
Bilayer graphene can exhibit deformations such that the two graphene sheets are locally detached from each other resulting in a structure consisting of domains with different van der Waals inter-layer coupling. Here we investigate how the presence of these domains affects the transport properties of bilayer graphene. We derive analytical expressions for the transmission probability, and the corresponding conductance, across walls separating different inter-layer coupling domains. We find that the transmission can exhibit a valley-dependent layer asymmetry and that the domain walls have a considerable effect on the chiral tunnelling properties of the charge carriers. We show that transport measurements allow one to obtain the strength with which the two layers are coupled. We perform numerical calculations for systems with two domain walls and find that the availability of multiple transport channels in bilayer graphene significantly modifies the conductance dependence on inter-layer potential asymmetry.
双层石墨烯可能会出现形变,使得两个石墨烯片层在局部相互分离,从而形成一种由具有不同范德华层间耦合的区域组成的结构。在此,我们研究这些区域的存在如何影响双层石墨烯的输运性质。我们推导了穿过分隔不同层间耦合区域的壁的传输概率及相应电导的解析表达式。我们发现,传输可能表现出与谷相关的层不对称性,并且区域壁对电荷载流子的手性隧穿性质有相当大的影响。我们表明,输运测量能够使人们获得两层耦合的强度。我们对具有两个区域壁的系统进行了数值计算,发现双层石墨烯中多个输运通道的存在显著改变了电导对层间势不对称性的依赖关系。