论文标题
转移矩阵方法的分层动力电导率 - 应用于N层石墨烯
Layered Dynamical Conductivity for a Transfer Matrix Method -- Application to an N-layer Graphene
论文作者
论文摘要
我们通过制定每一层的动态电导率来计算$ n $ layer石墨烯的光学性质。当电磁场位于特定层并与计算出的标准电导率不同时，假设所有层中的均匀场均与标准电导率不同时，这是电导率。通过将这些电导率与转移矩阵方法相结合，我们考虑了由内部反射引起的电磁场的空间变化。从两个电导率获得的结果表明，源自层间电子交互的相似峰结构出现在任何$ n $的$ n $ layer石墨烯中。该峰是AB堆叠固有的，对于AA堆叠而没有看到，并且对应于足够大的$ n $的峰被认为是天然石墨的峰。我们还对高压下高度定向的热解石墨和天然石墨的现有实验结果做出了物理解释。尽管分层的电导率低估了石墨在峰下方的光子能量上的反射率，但我们将表明分歧归因于层间相互作用引起的非局部电导率。具有分层电导率的计算对于了解局部对光的响应很有用，并且可以通过通过层间电子相互作用与我们最近发现的通用层数进行校正来进一步验证。
We calculated the optical properties of an $N$-layer graphene by formulating the dynamical conductivity of each layer. This is the conductivity when an electromagnetic field is localized at a particular layer and differs from the standard conductivity calculated assuming a uniform field throughout all layers. By combining these conductivities with a transfer matrix method, we took into account the spatial variation of the electromagnetic field caused by internal reflections. The results obtained from the two conductivities show that similar peak structures originating from the interlayer electronic interaction appear in reflectance of an $N$-layer graphene at any $N$. The peak is inherent to the AB stacking and is not seen for the AA stacking, and the peak corresponding to a sufficiently large $N$ is considered to the one observed for natural graphite. We also gave physical explanations of the existing experimental results on highly oriented pyrolytic graphite and natural graphite under high pressure. Although a layered conductivity underestimates the reflectance of graphite at photon energies below the peak, we will show that the disagreement is attributed to a nonlocal conductivity caused by interlayer interaction. The calculations with layered conductivity are useful in knowing the local response to light and may be further validated by an observation of a correction by interlayer electronic interaction to the universal layer number that we have discovered recently.
