含Stone-Wales缺陷zigzag型石墨烯纳米带的电学和光学性能研究

本文采用基于密度泛函理论的第一性原理对zigzag型石墨烯纳米带中含有不同Stone-Wales缺陷的电子结构特性和光学性能进行研究. 考虑了两种模型:不计电子自旋和考虑电子自旋的情况.研究发现:不计电子自旋情况下,含对称Stone-Wales缺陷的石墨烯纳米带在缺陷区域出现了凹凸不平的折皱构型,两种不同的Stone-Wales缺陷都引起了电荷的重新分布.考虑电子自旋时,Stone-Wales缺陷的引入对石墨烯纳米带自旋密度有显著影响,也引起了不同自旋的电子态密度的变化.进一步研究了纳米带的光学性能,发现 关键词： 石墨烯纳米带 Stone-Wales缺陷 电子结构 光学性能

Electronic and optical properties of zigzag graphene nanoribbon with Stone-Wales defect

Using the first principle based on the density-functional theory, we have studied the electronic structures and optical properties of zigzag graphene nanoribbon with different Stone-Wales defects. We take two kinds of models, namely that with and without spin polarization, into consideration. The results suggest that graphene nanoribbon with symmetrical Stone-Wales defect has the concavo-convex geometry structure in the defective region without considering spin polarization, both kinds of Stone-Wales defects give rise to the charge redistribution. The spin density of graphene nanoribbon with Stone-Wales defects is obviously affected by considering spin polarization, which leads to the changes of density of states for different kinds of spin. We have further investigated the optical properties of the graphenen nanoribbons; it was found that the peaks of absorption and reflectance have significent changes in the graphene nanoribbon with the presence of Stone-Wales defects, and red shift is observed when compared with the perfect graphene nanoribbon.