Three-dimensional valley-contrasting sound
Spin and valley are two fundamental properties of electrons in crystals. The similarity between them is well understood in valley-contrasting physics established decades ago in two-dimensional (2D) materials like graphene-with broken inversion symmetry, the two valleys in graphene exhibit opposite o...
| Main Authors: | , , , , , , , , , , |
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| Format: | Journal Article |
| Language: | English |
| Published: |
2024
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| Subjects: | |
| Online Access: | https://hdl.handle.net/10356/180458 |
| _version_ | 1826128129753612288 |
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| author | Xue, Haoran Ge, Yong Cheng, Zheyu Guan, Yi-Jun Zhu, Jiaojiao Zou, Hong-Yu Yuan, Shou-Qi Yang, Shengyuan A. Sun, Hong-Xiang Chong, Yidong Zhang, Baile |
| author2 | School of Physical and Mathematical Sciences |
| author_facet | School of Physical and Mathematical Sciences Xue, Haoran Ge, Yong Cheng, Zheyu Guan, Yi-Jun Zhu, Jiaojiao Zou, Hong-Yu Yuan, Shou-Qi Yang, Shengyuan A. Sun, Hong-Xiang Chong, Yidong Zhang, Baile |
| author_sort | Xue, Haoran |
| collection | NTU |
| description | Spin and valley are two fundamental properties of electrons in crystals. The similarity between them is well understood in valley-contrasting physics established decades ago in two-dimensional (2D) materials like graphene-with broken inversion symmetry, the two valleys in graphene exhibit opposite orbital magnetic moments, similar to the spin-1/2 behaviors of electrons, and opposite Berry curvature that leads to a half topological charge. However, valley-contrasting physics has never been explored in 3D crystals. Here, we develop a 3D acoustic crystal exhibiting 3D valley-contrasting physics. Unlike spin that is fundamentally binary, valley in 3D can take six different values, each carrying a vortex in a distinct direction. The topological valley transport is generalized from the edge states of 2D materials to the surface states of 3D materials, with interesting features including robust propagation, topological refraction, and valley-cavity localization. Our results open a new route for wave manipulation in 3D space. |
| first_indexed | 2025-03-09T14:44:55Z |
| format | Journal Article |
| id | ntu-10356/180458 |
| institution | Nanyang Technological University |
| language | English |
| last_indexed | 2025-03-09T14:44:55Z |
| publishDate | 2024 |
| record_format | dspace |
| spelling | ntu-10356/1804582024-10-14T15:35:14Z Three-dimensional valley-contrasting sound Xue, Haoran Ge, Yong Cheng, Zheyu Guan, Yi-Jun Zhu, Jiaojiao Zou, Hong-Yu Yuan, Shou-Qi Yang, Shengyuan A. Sun, Hong-Xiang Chong, Yidong Zhang, Baile School of Physical and Mathematical Sciences Centre for Disruptive Photonic Technologies (CDPT) Physics Acoustic crystal Edge state Spin and valley are two fundamental properties of electrons in crystals. The similarity between them is well understood in valley-contrasting physics established decades ago in two-dimensional (2D) materials like graphene-with broken inversion symmetry, the two valleys in graphene exhibit opposite orbital magnetic moments, similar to the spin-1/2 behaviors of electrons, and opposite Berry curvature that leads to a half topological charge. However, valley-contrasting physics has never been explored in 3D crystals. Here, we develop a 3D acoustic crystal exhibiting 3D valley-contrasting physics. Unlike spin that is fundamentally binary, valley in 3D can take six different values, each carrying a vortex in a distinct direction. The topological valley transport is generalized from the edge states of 2D materials to the surface states of 3D materials, with interesting features including robust propagation, topological refraction, and valley-cavity localization. Our results open a new route for wave manipulation in 3D space. Ministry of Education (MOE) National Research Foundation (NRF) Published version This work was supported by the Singapore National Research Foundation Competitive Research Program (NRF-CRP23-2019- 0005, NRF-CRP23- 2019- 0007, and NRF-CRP29- 2022-0003) (to Y.C. and B.Z.), Singapore National Research Foundation investigatorship (NRF-NRFI08-2022-0001) (to Y.C.), Singapore Ministry of education Academic Research Tier 2 grant (MOE-T2EP50123-0007) (to B.Z.), National Natural Science Foundation of China (12274183 and 12174159) (to H.-X.S. and Y.G.), National Key Research and development Program of China (2020YFc1512403) (to S.-Q.Y.), and the Start-up Fund and the Direct Grant (4053675) of the Chinese University of Hong Kong (to H.X.). 2024-10-08T04:37:39Z 2024-10-08T04:37:39Z 2024 Journal Article Xue, H., Ge, Y., Cheng, Z., Guan, Y., Zhu, J., Zou, H., Yuan, S., Yang, S. A., Sun, H., Chong, Y. & Zhang, B. (2024). Three-dimensional valley-contrasting sound. Science Advances, 10(37), eadp0377-. https://dx.doi.org/10.1126/sciadv.adp0377 2375-2548 https://hdl.handle.net/10356/180458 10.1126/sciadv.adp0377 39259802 2-s2.0-85204167615 37 10 eadp0377 en NRF-CRP23-2019-0005 NRF-CRP23-2019-0007 NRF-CRP29-2022-0003 NRF-NRFI08-2022-0001 MOE-T2EP50123-0007 Science Advances © 2024 the Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works. Distributed under a creative commons Attribution nonCommercial license 4.0 (CC BY-NC). application/pdf |
| spellingShingle | Physics Acoustic crystal Edge state Xue, Haoran Ge, Yong Cheng, Zheyu Guan, Yi-Jun Zhu, Jiaojiao Zou, Hong-Yu Yuan, Shou-Qi Yang, Shengyuan A. Sun, Hong-Xiang Chong, Yidong Zhang, Baile Three-dimensional valley-contrasting sound |
| title | Three-dimensional valley-contrasting sound |
| title_full | Three-dimensional valley-contrasting sound |
| title_fullStr | Three-dimensional valley-contrasting sound |
| title_full_unstemmed | Three-dimensional valley-contrasting sound |
| title_short | Three-dimensional valley-contrasting sound |
| title_sort | three dimensional valley contrasting sound |
| topic | Physics Acoustic crystal Edge state |
| url | https://hdl.handle.net/10356/180458 |
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