标题： 石墨烯σ带中的强电子-声子耦合 显示英文标题

标题： Strong electron-phonon coupling in the sigma band of graphene

摘要： 第一性原理研究石墨烯中的电子-声子耦合预测，$\sigma$带的耦合强度很高，$\lambda$值可达 0.9。 在$\sigma$带顶部附近，$\lambda$被发现为$\approx 0.7$。 这个值与最近通过角分辨光电子能谱观察到的$\sigma$带色散中的台阶一致。 尽管来自$\sigma$带的光电子能谱强度受亚晶格干涉的矩阵元影响很大，但第一布里渊区和相邻布里渊区的数据中这些影响存在显著差异。 这可以用来区分矩阵元和电子-声子耦合的影响。 使用Kramers-Kronig变换对实验确定的复自能进行严格分析，进一步支持了将观察到的台阶归因于强电子-声子耦合，并得到一个耦合常数为$0.6(1)$，与计算结果高度一致。 显示英文摘要

摘要： First-principles studies of the electron-phonon coupling in graphene predict a high coupling strength for the $\sigma$ band with $\lambda$ values of up to 0.9. Near the top of the $\sigma$ band, $\lambda$ is found to be $\approx 0.7$. This value is consistent with the recently observed kinks in the $\sigma$ band dispersion by angle-resolved photoemission. While the photoemission intensity from the $\sigma$ band is strongly influenced by matrix elements due to sub-lattice interference, these effects differ significantly for data taken in the first and neighboring Brillouin zones. This can be exploited to disentangle the influence of matrix elements and electron-phonon coupling. A rigorous analysis of the experimentally determined complex self-energy using Kramers-Kronig transformations further supports the assignment of the observed kinks to strong electron-phonon coupling and yields a coupling constant of $0.6(1)$, in excellent agreement with the calculations.