论文标题
扭曲的双层石墨烯网络模型中的手性曲折模式和平板
Chiral zigzag modes and flatbands in network models of twisted bilayer graphene
论文作者
论文摘要
我们为山谷大厅的三角网络构建了一种现象学散射理论，该理论是在层间偏置下扭曲的双层石墨烯中产生的。至关重要的是，我们的网络模型包括在同一山谷内的不同山谷大厅和旋转之间散射。我们表明，在没有正向散射的情况下，对称性将网络模型降低为单个参数，该参数在嵌套的费米表面和悬带之间插值，可以分别以一维手性曲折模式和封闭的三角轨道来理解。我们证明了单位性和对称性如何约束锯齿形模式之间的耦合，这对实验中观察到的干扰振荡的性质具有重要意义。
We construct a phenomenological scattering theory for the triangular network of valley Hall states that arises in twisted bilayer graphene under interlayer bias. Crucially, our network model includes scattering between different valley Hall states within the same valley and spin. We show that in the absence of forward scattering, symmetries reduce the network model to a single parameter that interpolates between a nested Fermi surface and flatbands, which can be understood in terms of one-dimensional chiral zigzag modes and closed triangular orbits, respectively. We demonstrate how unitarity and symmetry constrain the couplings between zigzag modes, which has important implications on the nature of interference oscillations observed in experiments.
