一维准晶体的电子性质

Electronic Properties of 1-D Quasicrystals

本文对一维准晶体的on-site模型做了更接近实际的修正,把电子的hoppingmatrix elements的差异考虑在内,建立一个混合模型。用负本征值理论计算能谱,用EDWW方法计算本征态,得到一系列新结果。在T_2/T_2<1时能带为二主带结构。在1≤T_2/T_1<2.6时为四主带结构,与on-site模型所得的结果相同。在2.6<T_2/T_1<3之间时为三主带结构,而T_2/T_2>3以后则是一种新的四主带结构。T_2/T_1=τ时,B带中全部的态都是延展态。态的局域性质与此值T_2/T_1有关,同一个编号的激发态,T_2/T_1不同时,局域性质会不同。

In this papar, the electronic properties of Fibonacci quasicryotals are studied. From the tight binding Hamiltonian, We consider to the difference of the nearest neighbor hopping matrix elements from the on-site·model and establish the mixture model, the Dean method has been used for solving eigenenergies and the EDWW method for solving eigenfuunctions. A number of new results have benn oftained·When T_2/T_1<1, the gross band is 2-band structure. When 1≤T_2/T_1<2.6, the gross bandrstructure is same as for on-site model. After T_2/T_1>3, the B-band of rhe ou-site model is divided into two sub-bauds. One of the sub-bauds vombines with the lower AA-band to form the new BAA-baud. When T_2/T_1=τ, the resutls of IPR aud wavefuuctious show that the states of B-band are exteuded, the effect of the difference of the n. n hopping matrix elemeut dramatically change the localized properties of the states.