论文标题
等离子kagome晶格中的高阶拓扑
Higher-order topology in plasmonic kagome lattices
论文作者
论文摘要
我们研究了kagome等离激子跨表面的拓扑特性，该曲线率二极法自然包含延迟的远距离相互作用。我们证明该系统通过计算威尔逊循环支持阻碍的原子极限阶段。然后，我们表征由等离激元纳米颗粒的亚波长阵列托管的拓扑边界模式的层次结构：一维边缘模式以及零维角模式。我们确定这些模式的特性，这些模式可牢固地限制在亚波长度尺度上的光，计算边缘和角模式下光子状态的局部密度，并通过非零轨道角度动量束激发在拓扑腔中对拓扑腔中的分离式角模式的选择性激发。
We study the topological properties of a kagome plasmonic metasurface, modelled with a coupled dipole method which naturally includes retarded long range interactions. We demonstrate the system supports an obstructed atomic limit phase through the calculation of Wilson loops. Then we characterise the hierarchy of topological boundary modes hosted by the subwavelength array of plasmonic nanoparticles: both one-dimensional edge modes as well as zero-dimensional corner modes. We determine the properties of these modes which robustly confine light at subwavelength scales, calculate the local density of photonic states at edge and corner modes frequencies, and demonstrate the selective excitation of delocalised corner modes in a topological cavity, through non-zero orbital angular momentum beam excitation.
