Experimental demonstration of anomalous Floquet topological insulator for sound.
Time-reversal invariant topological insulator is widely recognized as one of the fundamental discoveries in condensed matter physics, for which the most fascinating hallmark is perhaps a spin-based topological protection, the absence of scattering of conduction electrons with certain spins on matter surface. Recently, it has created a paradigm shift for topological insulators, from electronics to photonics, phononics and mechanics as well, bringing about not only involved new physics but also potential applications in robust wave transport. Despite the growing interests in topologically protected acoustic wave transport, T-invariant acoustic topological insulator has not yet been achieved. Here we report experimental demonstration of anomalous Floquet topological insulator for sound: a strongly coupled metamaterial ring lattice that supports one-way propagation of pseudo-spin-dependent edge states under T-symmetry. We also demonstrate the formation of pseudo-spin-dependent interface states due to lattice dislocations and investigate the properties of pass band and band gap states.
School of Physics, Huazhong University of Science and Technology, Luoyu road No. 1037, Wuhan, Hubei 430074, China.|Innovation Institute, Huazhong University of Science and Technology, Wuhan 430074, China.
Yu-Gui
YG
Peng
School of Physics, Huazhong University of Science and Technology, Luoyu road No. 1037, Wuhan, Hubei 430074, China.
Cheng-Zhi
CZ
Qin
School of Physics, Huazhong University of Science and Technology, Luoyu road No. 1037, Wuhan, Hubei 430074, China.
De-Gang
DG
Zhao
School of Physics, Huazhong University of Science and Technology, Luoyu road No. 1037, Wuhan, Hubei 430074, China.
Ya-Xi
YX
Shen
Key Laboratory of Noise and Vibration Research, Institute of Acoustics, Chinese Academy of Sciences, Beijing 100190, China.|School of Automation, Wuhan University of Technology, Wuhan 430063, China.
Xiang-Yuan
XY
Xu
Key Laboratory of Noise and Vibration Research, Institute of Acoustics, Chinese Academy of Sciences, Beijing 100190, China.
Ming
M
Bao
Key Laboratory of Noise and Vibration Research, Institute of Acoustics, Chinese Academy of Sciences, Beijing 100190, China.
Han
H
Jia
School of Physics, Huazhong University of Science and Technology, Luoyu road No. 1037, Wuhan, Hubei 430074, China.|Innovation Institute, Huazhong University of Science and Technology, Wuhan 430074, China.
Xue-Feng
XF
Zhu