本文是以 SSH 模型为基础，改变 SSH 模型中的四个参量：“ d ttt ,,, ' ? ”。根 据不同参量对应的能带图观察 SSH 模型中拓扑性的出现。SSH 模型是固体中的双链结构，在 磁通量 ? 的作用下，原子在双链上移动跳跃，在坐标空间原子的哈密顿量可以写出来，总体 上分为三部分：①粒子在两条链上平行于链方向上跳跃，用t来描述。②粒子在垂直链的方 向上从 a 链跳跃到 b 链，用 ' t 来描述。③加上对角隧道后，原子会在两条链上以对角线跳跃， 用 d t 来描述。 能带拓扑性的转变会出现在这些参量取特定值时，本来能带图上在一个周 期内的两条能量之间存在能隙，当参量满足一定条件时，这些能隙会闭合，即出现了边缘态， 体现出了系统的拓扑性。 在开方边界条件下，研究的现象是本来能隙中不该出现有能量， 却出现了能量。 本文通过改变上述 4 个参量的值，画出能带，分析这些参量的值对能带拓 扑性的影响，得出了一个结论：磁通 ? ，t 的值对能隙的关闭与否没有影响，t1 和 t2 的比 值真正地影响了能带的闭合与拓扑性的出现。在推广的 SSH 模型中，改变四个参量 ? ，t， t1，t2 的数值而保持 ?t td =1 不变，SSH 系统的能带将会闭合，系统在这时具有拓扑性

[Abstract] Based on SSH model, this paper changes four parameters of SSH model: “φ,t,t’,td”.The appearance of topology in SSH model is observed by band diagrams corresponding to different parameters. The SSH model is a double-chain structure in solids.Under the action of magnetic flux, atoms move and jump on double chains. The Hamiltonian of atoms in coordinate space can be written out as a whole.It is divided into three parts: (1) particles jump parallel to the direction of the chain in two chains and are described by t. (2) The square of particles in the vertical chain jump up from chain a too the other chain by t’ to describe. (3) With diagonal tunneling, atoms jump diagonally over two chains,using td to describe.The transition of energy band topology occurs when these parameters are given a specific value, and the band graph could have been plotted for a week.There are energy gaps between the two energies during the period. When the parameters satisfy certain conditions, these energy gaps will close, i.e. the edge states appear.It reflects the topology of the system. Under the open boundary condition, the phenomenon studied is that there should be no energy in the inherent energy gap.But there is energy. In this paper, by changing the values of the four parameters mentioned above, energy bands are drawn and the value pairs of these parameters are analyzed.The effect of flutter on the energy gap is discussed. A conclusion is drawn that the flux flux cone and the value of t have no effect on the closure of the energy gap, and the ratio of t1 to t 2.Values really affect the closure of bands and the appearance of topology. In the generalized SSH model, four parameters are changed, t,The values of t1 andt2 are maintained but keep their ratios constant .The energy band of SSH system will be closed without change, and the system will be topological at this time. [Extended] SSH Model, Topological Transition, Edge State, Gap Closure