Non-Hermitian waves in a continuous periodic model and application to photonic crystals
Non-Hermitian waves in a continuous periodic model and application to photonic crystals
复制标题
DOI：
10.1103/physrevresearch.4.023089
复制
发表时间：
2021-12
影响因子：
4.2
通讯作者：
Kazuki Yokomizo;Taiki Yoda;S. Murakami
中科院分区：
文献类型：
--
作者：
Kazuki Yokomizo;Taiki Yoda;S. Murakami
在一些非厄米系统中，本体的本征态在系统边界处是局域的。这被称为非厄米集肤效应，它主要是在离散系统中研究的。本文研究了连续周期模型中的非厄米集肤效应。在一维系统中，我们证明了所有特征态的局域化长度是相等的。此外，大系统的局域化长度和特征谱与开放边界条件的类型无关。在非厄米光子晶体中也发现了这些性质。连续周期模型中的这种显著行为可以用非布洛赫带理论来解释。通过构造复布洛赫波数的广义布里渊区，导出了开放边界条件下的局域长度和特征谱。此外，我们还证明了广义布里渊带还具有各种物理性质，如体边对应。
In some non-Hermitian systems, the eigenstates in the bulk are localized at the boundaries of the systems. This is called the non-Hermitian skin effect, and it has been studied mostly in discrete systems. In the present work, we study the non-Hermitian skin effect in a continuous periodic model. In a one-dimensional system, we show that the localization lengths are equal for all the eigenstates. Moreover, the localization length and the eigenspectra in a large system are independent of the types of open boundary conditions. These properties are also found in a non-Hermitian photonic crystal. Such remarkable behaviors in a continuous periodic model can be explained in terms of the non-Bloch band theory. By constructing the generalized Brillouin zone for a complex Bloch wave number, we derive the localization length and the eigenspectra under an open boundary condition. Furthermore we show that the generalized Brillouin zone also has various physical properties, such as bulk-edge correspondence.