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石墨烯材料需要经过不同的改性处理才能够在电子器件领域大规模应用,其中荷电就是一种非常有效的手段。文章通过第一性原理计算方法研究了带有少量电荷(电子或空穴)的单层石墨烯的电子和声子态特征,以及电-声子相互作用变化,发现荷电可以使费米能级发生移动,导致石墨烯展现金属特征。在石墨烯中引入电荷没有改变 z 轴方向声学的振动模,不会引起石墨烯的弯曲。在石墨烯中注入电子,可以引起声子模式的软化,电-声耦合强度随着引入的电子浓度增加而增强。由于引入电荷可以调节纵向光学的声子频率的变化并且导致一个更强的电-声子相互作用,推断通过该途径可以提高石墨烯中载流子的迁移率。“,”The modiifcation such as introducing charge is an effective means to make the graphene applicable in the ifeld of electronic devices. In this paper, the ifrst-principle calculation was performed to investigate the electronic and phononic band structures as well as the electron-phonon interaction in a monolayer graphene doped by small number of electrons or holes. It was found that, the charged graphene exhibits metallic character due to the shift of Fermi level. The introducing charge did not affect the variation of bending in graphene since the z-axis acoustic mode was unchanged. The abnormal softened phonon mode was observed for electron-doped graphene. The electron-phonon coupling was constantly enhanced with the increasing of charge concentration. It was concluded that, the carrier mobility in graphene can be improved since the doping adjusts the longitudinal optical phonon frequency and results in a stronger electron-phonon interaction.