The valley topological phases and transport phenomena for classical waves have attracted a great deal of attention. We realize valley spin Chern insulators in bilayer phononic crystals of a square lattice, whose topological invariants are described by the valley spin Chern numbers with the layer pseudospin. Four types of nontrivial topological phases can be realized by tuning the heights of cavities, which can result in the layer-mixed, layer-polarized, and layer-locked acoustic kink states. Interestingly, we experimentally demonstrate the anomalous layer-dependent partition transports of the acoustic kink states at the intersection constituted by the distinct topological phases. By taking advantage of the additional layer pseudospin, our systems provide a powerful platform from which to explore the intriguing properties of topological acoustics, and have potential applications for sound manipulation.

中文翻译：

---

声谷自旋陈绝缘子

经典波的谷拓扑相和输运现象引起了广泛关注。我们在方形晶格的双层声子晶体中实现了谷自旋陈绝缘体，其拓扑不变量由具有层赝自旋的谷自旋陈数描述。通过调整腔的高度可以实现四种类型的非平凡拓扑相，这可能导致层混合、层极化和层锁定声学扭结状态。有趣的是，我们通过实验证明了由不同拓扑相构成的交叉点处声学扭结状态的异常层相关分区传输。通过利用附加层赝自旋，我们的系统提供了一个强大的平台，可以从中探索拓扑声学的有趣特性，