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Dirac points and the transition towards Weyl points in three-dimensional sonic crystals
Boyang Xie1, Hui Liu1, Hua Cheng2
1The Key Laboratory of Weak Light Nonlinear Photonics, Ministry of Education, School of Physics, TEDA Institute of Applied Physics, and Renewable Energy Conversion and Storage Center, Nankai University, 300071, Tianjin, China.
Light, Science & Applications
|December 23, 2020
Summary
Researchers created 3D acoustic Dirac points in a sonic crystal, observing unique surface and interface states. These Dirac points can transform into Weyl points, inheriting exotic features for topological matter research.
Area of Science:
- Condensed Matter Physics
- Acoustic Metamaterials
- Topological Matter
Background:
- Three-dimensional (3D) Dirac crystals exhibit unique properties distinct from Weyl crystals.
- Understanding the evolution from 3D Dirac to Weyl crystals is crucial for advancing topological matter research.
- Topological semimetals offer a platform for exploring exotic physical phenomena.
Purpose of the Study:
- To realize 3D acoustic Dirac points in a hexagonal sonic crystal.
- To investigate the transition from 3D Dirac to Weyl points and the inheritance of their exotic features.
- To provide an experimental platform for studying 3D topological semimetals.
Main Methods:
- Band inversion in a hexagonal sonic crystal to create 3D acoustic Dirac points.
- Observation of surface states and helical interface states connecting Dirac points.
- Introduction of chiral hopping to transition Dirac points into Weyl points.
Main Results:
- Successfully realized a pair of 3D acoustic Dirac points.
- Observed surface states and helical interface states associated with the Dirac points.
- Demonstrated the transformation of Dirac points into Weyl points, with inherited exotic features.
Conclusions:
- The hexagonal sonic crystal serves as an ideal platform for studying 3D topological semimetals.
- The transition from Dirac to Weyl points preserves exotic topological features.
- This research advances the understanding of topological phase transitions in 3D systems.
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