The calculation of energy gaps in small single-walled carbon nanotubes within a symmetry-adapted tight-binding model  

作　　者：杨杰 董全力 江兆潭 张杰 

机构地区：[1]Beijing National Laboratory for Condensed Matter Physics,Institute of Physics,Chinese Academy of Sciences [2]Department of Physics,Beijing Institute of Technology

出　　处：《Chinese Physics B》2010年第12期431-436,共6页中国物理B（英文版）

基　　金：Project supported by the National Natural Science Foundation of China (Grant Nos. 10774184 and 10974015);the National Basic Research Program of China (973 Program) (Grant No. 2007CB815101)

摘　　要：This paper studies in detail the electronic properties of the semimetallic single-walled carbon nanotubes by applying the symmetry-adapted tight-binding model. It is found that the hybridization of π-σ states caused by the curvature produces an energy gap at the vicinity of the Fermi level. Such effects are obvious for the small zigzag and chiral single-walled carbon nanotubes. The energy gaps decrease as the diameters and the chiral angles of the tubes increase, while the top of the valence band and the bottom of the conduction band of armchair tubes cross at the Fermi level. The numeral results agree well with the experimental results.This paper studies in detail the electronic properties of the semimetallic single-walled carbon nanotubes by applying the symmetry-adapted tight-binding model. It is found that the hybridization of π-σ states caused by the curvature produces an energy gap at the vicinity of the Fermi level. Such effects are obvious for the small zigzag and chiral single-walled carbon nanotubes. The energy gaps decrease as the diameters and the chiral angles of the tubes increase, while the top of the valence band and the bottom of the conduction band of armchair tubes cross at the Fermi level. The numeral results agree well with the experimental results.

关 键 词：single-walled carbon nanotube curvature effect rehybridization of orbitals 

分 类 号：O469[理学—凝聚态物理]