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arXiv 1903.03338physics.optics
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Kagome晶格中的Valley-Hall型二阶光子拓扑绝缘体

Valley-Hall-like second-order photonic topological insulators in Kagome lattice

Le Zhang

摘要:

在具有C3 v点群对称性的Kagome晶格光子晶体中设计了谷-霍尔型二阶光子拓扑绝缘体。光子晶体由纯电介质材料中的圆形空气孔组成。与传统的谷-霍尔光子拓扑绝缘体不同,该绝缘体具有量子化电极化的强度描述的拓扑不变量.通过调整结构尺寸可以实现拓扑转变,拓扑边态出现在不同拓扑相的光子晶体之间的界面,保持了谷-霍尔光子绝缘体的重要特性,如谷输运和小的后向散射。所提出的光子晶体也支持在斜角处的零维角态,显示其二阶拓扑绝缘体特征。本工作提出了在同一平台上实现拓扑保护反射抑制波导和局部腔的可能性。

英文摘要:

Valley-Hall-like second-order photonic topological insulators are designed in Kagome-lattice photonic crystals with C3v point-group symmetry. The photonic crystal consists of circular air holes in pure dielectric materials. Different from conventional valley-Hall photonic topological insulators characterized by valley Chern numbers, the proposed insulators have topological invariants described by quantized electric polarization. Topological transition can be realized by tuning the structural size and topological edge states appear at the interface between photonic crystals with different topological phases, preserving important features of valley-Hall photonic insulators such as valley transport with little backscattering. The proposed photonic crystal also support zero-dimensional corner states in oblique corners, showing its second-order topological insulator signature. This work presents the possibility to realize topologically protected reflection suppressed waveguides and local cavities in the same platform.

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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