Pseudospin-valley coupled edge states in a photonic topological insulator
Applied Physics
2018-12-18 v1 Mesoscale and Nanoscale Physics
Optics
Abstract
Pseudo-spin and valley degrees of freedom (DOFs) engineered in photonic analogues of topological insulators (TI) provide potential approaches to optical encoding and robust signal transport. Here we observe a ballistic edge state whose spin-valley indices are locked to the direction of propagation along the interface between a valley photonic crystal and a metacrystal emulating the quantum spin Hall effect. We demonstrate the inhibition of inter-valley scattering at a Y-junction formed at the interfaces between photonic TIs carrying different spin-valley Chern numbers. These results open up the possibility of using the valley DOF to control the flow of optical signals in 2D structures.
Keywords
Cite
@article{arxiv.1804.08707,
title = {Pseudospin-valley coupled edge states in a photonic topological insulator},
author = {Yuhao Kang and Xiaojun Cheng and Xiang Ni and Alexander B. Khanikaev and Azriel Z. Genack},
journal= {arXiv preprint arXiv:1804.08707},
year = {2018}
}