电荷掺杂诱导单层六方氮化硼片ZO模软化  

Charge-doping-induced ZO mode soft of h-BN monolayer

作　　者：杨巍[1] 侯春菊[1] 张旭[2] 

机构地区：[1]江西理工大学理学院,江西赣州341000 [2]江西理工大学材料科学与工程学院,江西赣州341000

出　　处：《江西理工大学学报》2014年第3期95-100,共6页Journal of Jiangxi University of Science and Technology

基　　金：江西省教育厅青年基金项目(GJJ11129);江西理工大学校级基金项目(jxxj12031)

摘　　要：基于密度泛函理论和密度泛函微扰理论,研究了电荷掺杂对单层六方氮化硼片(h-BN)红外活性的影响.研究发现h-BN片中具有红外活性的ZO模对电荷掺杂表现出强烈的软化行为,这不同于掺杂的石墨烯.而且ZO模对电子掺杂较空穴掺杂更敏感,且在K点较M点或Γ点软化得更强烈,频移高达193 cm-1.从原子振动图和ZO模能量差可以清楚地看到红外活性增强主要由ZO(K)模贡献,电荷掺杂引起的电子重新排布是红外活性增强的原因,这对设计具有强红外活性的电子器件具有很好的理论指导作用.Based on density functional theory and density functional perturbation theory, the paper investigates the infrared-active responses of h-BN sheet to charge doping. It is found that infrared-active ZO mode in the h-BN sheet presents dramatic softening behavior, which is different from that of doped graphene. Moreover, ZO mode is more sensitive to electron doping than hole doping, and the softening of ZO mode is more sensitive at K point than at M or Г point, with the frequency up to 193 cm-1. From the atomic displacements and the energy difference of ZO mode, it can be seen that the ZO （K） mode is the main reason for the infrared-active enhancement, resulting from the modification charge of density induced by doping. The results theoretically point out a new way to design infrared-active electronic device.

关 键 词：ZO模软化 电荷掺杂 单层六方氮化硼片 第一性原理计算 

分 类 号：O469[理学—凝聚态物理]