研究背景：类比于晶态固体，声子晶体是由结构单元周期性排列而成的人工声波带隙材料。该方向属于凝聚态物理和声学研究的前沿交叉领域。基本研究思路是：借助固体能带论的理论框架，设计人工单元结构、剪裁声波色散曲线，探索声子晶体调控声波的新原理、新效应、新应用。最近，人们开始从对称性、能带拓扑分类等新视角深入理解声子晶体的带隙形成机制和通带传播特性，建立体态和边界态的密切关联。科学上，声子晶体拓扑物性研究可促成对经典、量子拓扑物态统一完备的理解，甚至领先于量子体系提出、发现一些有趣的拓扑物理效应和现象；应用上，这类基础研究可为研制性能卓越的新型声功能器件提供理论依据和知识储备。邱春印教授在该前沿交叉方向做了一系列具有国际影响力的研究工作，理论提出并实验验证了一些极具声学特色的拓扑体系，观察到了一些独特的经典波拓扑输运现象，例如无反射的拓扑表面态负折射效应(Nature 2018)、无反射的谷态拓扑输运（Nat.Phys.2018）、声朗道量子化效应等（Nat.Phys.2019）。

代表性论文（*通讯作者）：

1.     Q. Zhang,† Y. Leng,† L. Xiong, Y. Li, K. Zhang, L. Qi, and C. Qiu*, Construction and Observation of Flexibly Controllable  High-Dimensional Non-Hermitian Skin Effects, Adv. Mater. http: 10.1002/adma.202403108

2.   H. Qiu, Y. Li, Q. Zhang, and C. Qiu*, Discovery of Higher-Order Nodal Surface Semimetals, Phys. Rev. Lett. 132, 186601 (2024).

3.     L. Liu, T. Li, Q. Zhang, M. Xiao, and C. Qiu*, Universal Mirror-Stacking Approach for Constructing Topological Bound States in the Continuum, Phys. Rev. Lett. 130, 106301 (2023).

4.     H. Qiu, Q. Zhang, T. Liu, X. Fan, F. Zhang, and C. Qiu*, Minimal non-abelian nodal braiding in ideal metamaterials, Nature Communications 14: 1261 (2023).

5.     Q. Zhang, Y. Li, H. Sun, X. Liu, L. Zhao, X. Feng, X. Fan, and C. Qiu*, Observation of Acoustic Non-Hermitian Bloch Braids and Associated Topological Phase Transitions, Phys. Rev. Lett. 130, 017201 (2023). Selected as “Editors’ Suggestion” and “Cover”.

6.     J. Du^†, T. Li^†, X. Fan, Q. Zhang, and C. Qiu*, Acoustic Realization of Surface-Obstructed Topological Insulators, Phys. Rev. Lett. 128, 224301 (2022).

7.     X. Fan, T. Xia, H. Qiu, Q. Zhang, and C. Qiu*, Tracking Valley Topology with Synthetic Weyl Paths, Phys. Rev. Lett. 128, 216403 (2022).

8.     T. Li^†, J. Du^†, Q. Zhang^†, Y. Li, F. Zhang*, and C. Qiu*, Acoustic Möbius insulators from projective symmetry, Phys. Rev. Lett. 128, 116803 (2022). Selected as “Editors’ Suggestion” and “Physics-Viewpoints”.

9.     L. Ye, C. Qiu*, M. Xiao*, T. Li, J. Du, M. Ke*, and Z. Liu*, Topological dislocation modes in three-dimensional acoustic topological insulators, Nature Communications, 13: 508 (2022). 

10.  H. Qiu, M. Xiao, F. Zhang, and C. Qiu*, Higher-order Dirac Sonic Crystals, Phys. Rev. Lett. 127, 146601 (2021).

11.  Y. Qi, C. Qiu*, M. Xiao*, H. He, M. Ke, and Z. Liu, Acoustic realization of quadrupole topological insulators, Phys. Rev. Lett. 124, 206601 (2020).

12.  H. He, C. Qiu*, X. Cai, M. Xiao, M. Ke, F. Zhang, and Z. Liu*, Observation of quadratic Weyl points and double-helicoid arcs, Nature Communications, 11:1820 (2020).

13.  M. Xiao, L. Ye, C. Qiu*, H. He, Z. Liu^* and S. Fan^*, Experimental demonstration of acoustic semimetal with topologically charged nodal surface, Science Advance 6 : eaav2360 (2020).

14.  X. Fan, C. Qiu*, Y. Shen, H. He, M. Xiao, M. Ke, and Z. Liu*, Probing Weyl physics with one-dimensional sonic crystals, Phys. Rev. Lett. 122, 136802 (2019).

15.  X. Wen, C. Qiu*, Y. Qi, L. Ye, M. Ke, F. Zhang, and Z. Liu, Acoustic Landau quantization and quantum Hall-like edge states, Nature Physics 15, 352–356 (2019).  This work was highlighted by Nature Physics “News and Views”.

16.  H. He, C. Qiu*, L. Ye, X. Cai, X. Fan, M. Ke, F. Zhang, and Z. Liu*, Topological negative refraction of surface acoustic waves in a Weyl phononic crystal, Nature 560, 61-64 (2018).-- Highlighted by IOP ‘Physics World’ and Nature ‘News and Views’, and others.

17.  J. Lu, C. Qiu*, W. Deng, X. Huang, F. Li, F. Zhang, S. Chen,* and Z. Liu*, Valley Topological Phases in Bilayer Sonic Crystals, Phys. Rev. Lett. 120, 116802 (2018).

18.  J. Lu, C. Qiu*, L. Ye, X. Fan, M. Ke, F. Zhang, and Z. Liu*, Observation of topological valley transport of sound in sonic crystals, Nature Physics, 13, 369-374 (2017). Hot & highly cited paper.

19.  J. Lu, C. Qiu*, M. Ke, and Z. Liu*, Valley vortex states in sonic crystals, Phys. Rev. Lett. 116, 093901 (2016) [Selected as Editors’ Suggestion in PRL and Research Highlight in Nature Physics 12, 287 (2016), and also highlighted by IOP ‘Physics World’].

20.  Z. He, H. Jia, C. Qiu*, S. Peng, X. Mei, F. Cai, P. Peng, M. Ke, and Z. Liu*, Acoustic Transmission Enhancement through a Periodically Structured Stiff Plate without Any Opening, Phys. Rev. Lett. 105, 074301 (2010).