标题： 石墨烯/氮化硼扶手椅形横向异质结构的电子结构和光学吸收的第一性原理和模型研究 显示英文标题

标题： Electronic structure and optical absorption of armchair graphene/boron nitride lateral heterostructures from first principles and models

摘要： 我们研究了由石墨烯和六方氮化硼交替的扶手椅形纳米带组成的横向异质结构的电子和光学性质。 我们采用从头算理论（DFT 和 G0W0 方法）以及一种最初用于研究孤立纳米带带隙宽度的紧束缚梯子模型。 在研究界面处的电荷分布后，我们确定了带隙附近态的性质，并仔细分析了它们随系统特征尺寸的变化情况（石墨烯纳米带的宽度 N 和氮化硼纳米带的宽度 L）。 我们还揭示了石墨烯和氮化硼之间的界面如何改变两种材料的电子性质，相对于相应的孤立纳米带而言。 最后，我们通过推导异质结构的特定选择规则，并在独立粒子和随机相位近似下从头计算光谱，讨论了这些系统的光吸收特性。 显示英文摘要

摘要： We investigate the electronic and optical properties of lateral heterostructures made of alternated armchair ribbons of graphene and hexagonal boron nitride. We employ ab initio theories (DFT and the G0W0 method) as well as a tight-binding ladder model originally introduced to study the gapwidth of isolated nanoribbons. After investigating the charge distribution across the interface, we identify the nature of the states around the gap and scrutinize their evolution as a function of the characteristic dimensions of the system (the graphene ribbons' width N and the boron nitride ribbons' width L). We also disclose how the very interface between graphene and boron nitride changes the electronic properties of both materials with respect to the corresponding isolated nanoribbons. Finally we discuss the light absorption properties of these systems by deriving specific selection rules for the heterostructures and calculating spectra from first principles in the independent particle and the random phase approximations