arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 2303.04523cond-mat.mes-hallcond-mat.mtrl-sci
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在扩展的 Su-Schrieffer-Heeger 模型中构造任意缠绕数和 Chern 数的拓扑相

Engineering topological phases of any winding and Chern numbers in extended Su-Schrieffer-Heeger models

Rakesh Kumar Malakar, Asim Kumar Ghosh

AI总结:

通过在扩展的 SSH 模型中引入进一步邻居跃迁项,实现了任意缠绕数和 Chern 数的拓扑相构造,并揭示了特定非线性项下的淬火动力学、边缘态交叉及虚假拓扑相现象。

摘要:

通过添加距离可变的进一步邻居跃迁项,在 Su-Schrieffer-Heeger (SSH) 模型中找到了构造任意所需缠绕数和 Chern 数的拓扑相的简单途径。已知标准 SSH 模型产生缠绕数 $ν=1$ 的单一拓扑相。本研究展示了在保持反转、粒子-空穴和手征对称性的单一进一步邻居项存在下,如何生成任意值的拓扑相,例如 $ν=±1,±2,±3,\cdots$。研究了在特定非线性项存在下拓扑相和平庸相的淬火动力学。此前曾引入另一种 SSH 模型版本,其具有附加的调制最近邻和次近邻跃迁参数,表现出以 Chern 数 $\mathcal C=±1$ 为特征的单一拓扑相。该模型中反转、粒子-空穴和手征对称性的标准形式被打破。本文在多种参数化存在下研究了该模型,其中在特殊情况下,发现系统产生一系列具有 Chern 数 $\mathcal C=±1,±2,±3,\cdots$ 的相。在另一种参数化中,在平庸相和拓扑相中均发现边缘态能量线内的多次交叉。为每种情况绘制了拓扑相图。还报告了虚假拓扑相的出现。

英文摘要:

Simple route of engineering topological phases for any desired value of winding and Chern numbers is found in the Su-Schrieffer-Heeger (SSH) model by adding a further neighbor hopping term of varying distances. It is known that the standard SSH model yields a single topological phase with winding number, $ν=1$. In this study it is shown that how one can generate topological phases with any values of winding numbers, for examples, $ν=\pm 1,\pm 2,\pm 3,\cdots,$ in the presence of a single further neighbor term which preserves inversion, particle-hole and chiral symmetries. Quench dynamics of the topological and trivial phases are studied in the presence of a specific nonlinear term. Another version of SSH model with additional modulating nearest neighbor and next-nearest-neighbor hopping parameters was introduced before which exhibit a single topological phase characterized by Chern number, $\mathcal C=\pm 1$. Standard form of inversion, particle-hole and chiral symmetries are broken in this model. Here this model has been studied in the presence of several types of parametrization among which, for a special case the system is found to yield a series of phases with Chern numbers, $\mathcal C=\pm 1,\pm 2,\pm 3,\cdots.$ In another parametrization, multiple crossings within the edge states energy lines are found in both trivial and topological phases. Topological phase diagrams are drawn for every case. Emergence of spurious topological phases is also reported.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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