Valley topological materials, in which electrons possess valley pseudospin, have attracted a growing interest recently. The additional valley degree of freedom offers a great potential for its use in information encoding and processing. The valley pseudospin and valley edge transport have been investigated in photonic and phononic crystals for electromagnetic and acoustic waves, respectively. In this work, by using a micromanufacturing technology, valley topological materials are fabricated on silicon chips, which allows the observation of gyral valley states and valley edge transport for elastic waves. The edge states protected by the valley topology are robust against the bending and weak randomness of the channel between distinct valley Hall phases. At the channel intersection, a counterintuitive partition of the valley edge states manifests for elastic waves, in which the partition ratio can be freely adjusted. These results may enable the creation of on-chip high-performance micro-ultrasonic materials and devices.

电子具有谷假自旋的谷拓扑材料最近引起了越来越多的兴趣。附加的谷底自由度为其在信息编码和处理中的使用提供了巨大的潜力。已分别在光子和声子晶体中研究了谷假自旋和谷边缘传输，以获取电磁波和声波。在这项工作中，通过使用微制造技术，在硅芯片上制造了谷底拓扑材料，从而可以观察回旋谷底状态和谷底边缘传输弹性波。受谷形拓扑保护的边缘状态对于不同的谷形霍尔相之间的通道的弯曲和弱随机性具有鲁棒性。在通道交叉口，对于弹性波，出现了谷边缘状态的反直觉的划分，其中可以自由地调整划分比率。这些结果可以实现片上高性能微超声材料和器件的创建。