TY - JOUR
T1 - Routing Edge States in an Anisotropic Elastic Topological Insulator
AU - An, Shuowei
AU - Liu, Tuo
AU - Chen, Yafeng
AU - Cheng, Li
AU - Zhu, Jie
N1 - Funding Information:
This work is supported by the Fundamental Research Funds for the Central Universities (Grant No. 22120220237), the National Natural Science Foundation of China (Grant No. 1210020421), and the Research Grants Council of Hong Kong SAR (Grant No. AoE/P-502/20).
Publisher Copyright:
© 2022 American Physical Society.
PY - 2022/11
Y1 - 2022/11
N2 - Topological insulators, protected by nontrivial band topology, exhibit backscattering-immune edge states, conducive to robust waveguiding with high efficiency. However, routing such robust edge states has been restricted by the isotropy in conventional unit cells respecting crystalline symmetries, such as C4v symmetry in a square lattice or C3 symmetry in a hexagonal lattice. We effectively tackle this issue by introducing anisotropic coupling into a square lattice. With theoretical prediction from the discrete mechanical model, we experimentally demonstrate that such anisotropy can enable distinctive topological phases along different directions, giving rise to directional edge states. In addition, when the bands along the two directions are topologically identical and untrivial, the coexisting edge states have distinctive frequency ranges, giving rise to the frequency-routed properties. Our work offers an effective strategy for the robust steering, filtering, detection, and transmission of elastic waves through tactical edge state routing.
AB - Topological insulators, protected by nontrivial band topology, exhibit backscattering-immune edge states, conducive to robust waveguiding with high efficiency. However, routing such robust edge states has been restricted by the isotropy in conventional unit cells respecting crystalline symmetries, such as C4v symmetry in a square lattice or C3 symmetry in a hexagonal lattice. We effectively tackle this issue by introducing anisotropic coupling into a square lattice. With theoretical prediction from the discrete mechanical model, we experimentally demonstrate that such anisotropy can enable distinctive topological phases along different directions, giving rise to directional edge states. In addition, when the bands along the two directions are topologically identical and untrivial, the coexisting edge states have distinctive frequency ranges, giving rise to the frequency-routed properties. Our work offers an effective strategy for the robust steering, filtering, detection, and transmission of elastic waves through tactical edge state routing.
UR - http://www.scopus.com/inward/record.url?scp=85143196467&partnerID=8YFLogxK
U2 - 10.1103/PhysRevApplied.18.054071
DO - 10.1103/PhysRevApplied.18.054071
M3 - Journal article
AN - SCOPUS:85143196467
SN - 2331-7019
VL - 18
JO - Physical Review Applied
JF - Physical Review Applied
IS - 5
M1 - 054071
ER -