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arXiv · 1907.04674

Pseudospin-Polarized Topological Line Defects in Dielectric Photonic Crystals

Menglin L. N. Chen·Li Jun Jiang·Zhihao Lan·Wei E. I. Sha
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Abstract

Electromagnetic topological insulators have been explored extensively due to the robust edge states they support. In this work, we propose a topological electromagnetic system based on a line defect in topologically nontrivial photonic crystals (PCs). With a finite-difference supercell approach, modal analysis of the PCs structure is investigated in detail. The topological line-defect states are pseudospin polarized and their energy flow directions are determined by the corresponding pseudospin helicities. These states can be excited by using two spatially-symmetric line-source arrays carrying orbital angular momenta. The feature of the unidirectional propagation is demonstrated and it is stable when disorders are introduced to the PCs structure.

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Menglin L. N. Chen, Li Jun Jiang, Zhihao Lan, Wei E. I. Sha. 2019-07-10. Pseudospin-Polarized Topological Line Defects in Dielectric Photonic Crystals. https://doi.org/10.1109/tap.2019.2934816

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