化学吸附对石墨烯物性的影响

项目名称： 化学吸附对石墨烯物性的影响

项目编号： No.11274285

项目类型： 面上项目

立项/批准年度： 2013

项目学科： 数理科学和化学

项目作者： 石勤伟

作者单位： 中国科学技术大学

项目金额： 70万元

中文摘要： 石墨烯表面的化学吸附原子将会在狄拉克点附近形成共振能级，由此带来的共振散射将会对石墨烯的电子结构产生很大的修正。本项目旨在研究化学吸附基团，如氢基、甲基等，对表面吸附的石墨烯的电子结构和量子输运性质的影响。利用近期我们发展的动量空间态密度计算方法，通过大规模数值模拟计算体系准粒子谱函数。由此，我们可以准确的得到体系的准粒子能量色散关系，进而研究共振散射是如何在狄拉克点附近打开能隙的。众所周知，如何有效的打开石墨烯的能隙为其将来在电子学上的应用具有极为重要的意义。此外，我们将结合单参数标度理论和实空间严格对角化的方法，分析能隙中杂质能级的电子态的行为以及对输运性质和光电性质的影响。

中文关键词： 三维拓扑半金属；无序；准粒子性质；量子相变；

英文摘要： Graphene is two dimensional material with perfect electrical properties. Adatoms that are covalently bonded to graphene strongly perturb the elelctron structure of graphene and thus may be expected to create resonant states in the vicinity of the Dirac point. These resonant states induce strong scattering for electrons in the graphene. This project focus on studying how the resonant scattering affect electronic structure and quantum transport properties in graphene. With the help of our well-developed method, we can calculate the spectral function or density of states in momentum space accurately. Through the analysis of spectral function, we can obtain the effective energy dispersion of the adsorbated graphene. Gap-opening near the Dirac point induced by adatoms can be also clarified, which is very important for its future application in electronics. Moreover, we will study the impurity states in the gap and their effect on the transport and optical properties based on the one-parameter scaling hypothesis and exact diagonalization method.

英文关键词： Three-dimensional topological semimetal；disorder；quasiparticle properties；quantum phase transition；