TY - JOUR
T1 - Wave Steering by Relaying Interface States in a Valley-Hall-Derived Photonic Superlattice
AU - Chu, Hongchen
AU - Chen, Ze Guo
AU - Lai, Yun
AU - Ma, Guancong
N1 - Funding Information:
Z.-G.C. thanks Xiao Hu, Cheng He and Xiao-Chen Sun for helpful discussions. This work is supported by Hong Kong Research Grants Council (Grants No. 12302420, No. 12300419, No. 22302718, No. C6013-18G), National Natural Science Foundation of China (Grants No. 11922416, No. 11802256), and Hong Kong Baptist University (Grants No. RC-SGT2/18-19/SCI/006). Y. L. also acknowledges financial support from the National Key R&D Program of China (Grant No. 2020YFA0211300), the National Natural Science Foundation of China (Grant No. 11974176, 61671314).
Publisher Copyright:
© 2021 American Physical Society
PY - 2021/10
Y1 - 2021/10
N2 - Topological notions in physics have become a powerful perspective that leads to the discoveries of interface states. In this work, we present a scheme to steer waves by leveraging the properties of valley interface states (VISs) in a valley photonic crystal (VPC). Due to the chiral characteristics, the VISs deterministically possess either positive or negative dispersion relation, which can cause an obliquely incident wave to undergo a lateral shift. By stacking multiple VPC interfaces, the VIS-induced lateral shifts can relay in the transmitted wave towards the far side of incidence. By selectively engaging one type of VISs, the resultant outgoing wave appears to have undergone negative refraction. While this refraction can be flipped to positive by selectively exciting the other type of VISs with positive dispersion. This finding is verified in microwave experiments. Our scheme opens application scenarios for topological systems in wave manipulations.
AB - Topological notions in physics have become a powerful perspective that leads to the discoveries of interface states. In this work, we present a scheme to steer waves by leveraging the properties of valley interface states (VISs) in a valley photonic crystal (VPC). Due to the chiral characteristics, the VISs deterministically possess either positive or negative dispersion relation, which can cause an obliquely incident wave to undergo a lateral shift. By stacking multiple VPC interfaces, the VIS-induced lateral shifts can relay in the transmitted wave towards the far side of incidence. By selectively engaging one type of VISs, the resultant outgoing wave appears to have undergone negative refraction. While this refraction can be flipped to positive by selectively exciting the other type of VISs with positive dispersion. This finding is verified in microwave experiments. Our scheme opens application scenarios for topological systems in wave manipulations.
UR - http://www.scopus.com/inward/record.url?scp=85117227167&partnerID=8YFLogxK
U2 - 10.1103/PhysRevApplied.16.044006
DO - 10.1103/PhysRevApplied.16.044006
M3 - Journal article
AN - SCOPUS:85117227167
SN - 2331-7019
VL - 16
JO - Physical Review Applied
JF - Physical Review Applied
IS - 4
M1 - 044006
ER -