Authors: Ji-Qian Wang, Zi-Dong Zhang, Si-Yuan Yu, Hao Ge, Kang-Fu Liu, Tao Wu, Xiao-Chen Sun, Le Liu, Hua-Yang Chen, Cheng He, Ming-Hui Lu, Yan-Feng Chen
Published: 2022-03-14
DOI: 10.1038/s41467-022-29019-8
Source: Full article
AbstractStable and efficient guided waves are essential for information transmission and processing. Recently, topological valley-contrasting materials in condensed matter systems have been revealed as promising infrastructures for guiding classical waves, for they can provide broadband, non-dispersive and reflection-free electromagnetic/mechanical wave transport with a high degree of freedom. In this work, by designing and manufacturing miniaturized phononic crystals on a semi-infinite substrate, we experimentally realized a valley-locked edge transport for surface acoustic waves (SAWs). Critically, original one-dimensional edge transports could be extended to quasi-two-dimensional ones by doping SAW Dirac “semimetal” layers at the boundaries. We demonstrate that SAWs in the extended topological valley-locked edges are robust against bending and wavelength-scaled defects. Also, this mechanism is configurable and robust depending on the doping, offering various on-chip acoustic manipulation, e.g., SAW routing, focusing, splitting, and converging, all flexible and high-flow. This work may promote future hybrid phononic circuits for acoustic information processing, sensing, and manipulation.