一维具有近平带锯齿链模型的拓扑相变

发布时间：2018-04-03 03:35

本文选题：拓扑相变　切入点：光晶格　出处：《山西大学学报(自然科学版)》2017年03期

【摘要】：研究了一维具有周期性调制的锯齿链模型的近平带和拓扑相变问题。在无周期性调制情况下,标准的锯齿链模型出现平带的条件为沿着对角线方向的跃迁强度是沿着底线方向的2~(1/2)倍,但是此时平带为拓扑平庸的。引入周期性调制后,系统出现一系列近平带,且具有非零的整数陈数,具有拓扑非平庸的性质。通过改变调制强度,系统伴随着拓扑数和能隙的变化出现一系列拓扑相变。这一模型可以在现阶段冷原子系统中实现。
[Abstract]:In this paper, the near flat band and topological phase transition of one dimensional sawtooth chain model with periodic modulation are studied.In the case of no periodic modulation, the condition for the standard sawtooth chain model to appear flat band is that the intensity of transition along diagonal direction is 2 / 1 / 2 of that along the bottom line, but the flat band is topological mediocre at this time.When the periodic modulation is introduced, a series of near flat bands appear in the system, and the system has non-zero integer number, which has the property of topological non-mediocrity.By changing the modulation intensity, a series of topological transitions appear along with the changes of the topological number and the band gap.This model can be implemented in cold atomic systems at this stage.
【作者单位】：山西大学理论物理研究所;山西医科大学基础医学院物理教研室;
【基金】：国家自然科学基金(11604188) 山西省基础研究青年基金(2016021027)
【分类号】：O413;O469

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