The Study Of Electronic Properties Of Graphene Nanoribbons

Since2004by Novoselov et al. Prepared graphene, its topology has a great deal of research interest. Have excellent electron mobility in graphene, which will have a good prospect of application inelectronic devices such as single electron transistors, nano-polymer.Quasi-one-dimensional characteristics of the graphene nanoribbons can adjust the band gap of the nature of the use of nano-electronic devices of great significance. When GNRs geometry determined, how to adjust their electronic properties has also become the focus of attention. Graphene has very good strength, it can be used to exert force or uniaxial stress to change its electronic properties. We will use the tight-binding approximation, the theory of elasticity and the Harrison theory to study the characteristics of the electron spectrum and energy gap of armchair GNRs under uniaxial stress changes with the deformation parameters, calculated, respectively, consider the nearest neighbor, second nearest neighbor and three close neighbors of these three circumstances,The tight-binding method of armchair graphene nanoribbons by uniaxial stress along the length direction and subject to the direction of electron spectroscopy and the energy gap and the deformation. Along the two directions of strain with the width of the trend is the same strain must, difference is that the inflection point when the energy gap with the width of the change, consider the three close neighbors strain along the x direction of the inflection point will be to increase the width direction move, while the stress along the y direction, the turning point will decrease in the width direction of move certain width, the energy gap with the stress change in the width of the n=3m and width for n=3m+1, the energy gap with the change of stress is the opposite, consider the three neighbors, then will be the turning point, and the inflection point moves towards zero stress, the width of the n=3m+2, regardless of the energy gap along the y direction along the x direction or stress with stress change in a V shape, with the increase of stress in the compression energy gap is reduced, in the stretch under the energy gap is increased with increasing stress, and metallic armchair graphene nanoribbons changes. in both directions, is the bond length changes caused by the hopping integral and overlap integral caused. The electronic structure of graphene nanoribbons depends mainly on the geometric structure of the stress to change the geometric structure, the energy gap chang...