论文标题
一个维度
Non-Hermitian flatband generator in one dimension
论文作者
论文摘要
由于其有趣的属性和对扰动的敏感性，无散的乐队（平板带）已被积极研究，这使其成为异国情调状态的天然候选人。在近年来，在平行的非热系统中，它引起了广泛关注，这是对开放系统的简化描述，并以潜在的应用动机动机。特别是，在理论上和实验中研究了具有无分散能带的非亚米特系统。板带一般需要对哈密顿量进行微调或对称性保护。引入了许多方法来构建依赖于对称性或特定沮丧的几何形状的非热式平带，通常是受Hermitian模型启发的。我们讨论一种使用1d两个频段紧密结合网络的非热板构造的系统构建方法，以扩展用于系统地构建Hermitian平板的方法。我们表明，非武术案件接受了微调的，非对称的受保护的板带，并提供了比Hermitian案的更多类型的平带。
Dispersionless bands -- flatbands -- have been actively studied thanks to their interesting properties and sensitivity to perturbations, which makes them natural candidates for exotic states. In parallel non-Hermitian systems have attracted much attention in the recent years as a simplified description of open system with gain or loss motivated by potential applications. In particular, non-Hermitian system with dispersionless energy bands in their spectrum have been studied theoretically and experimentally. Flatbands require in general fine-tuning of Hamiltonian or protection by a symmetry. A number of methods was introduced to construct non-Hermitian flatbands relying either on a presence of a symmetry, or specific frustrated geometries, often inspired by Hermitian models. We discuss a systematic method of construction of non-Hermitian flatbands using 1D two band tight-binding networks as an example, extending the methods used to construct systematically Hermitian flatbands. We show that the non-Hermitian case admits fine-tuned, non-symmetry protected flatbands and provides more types of flatbands than the Hermitian case.
