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Updated: Dec 25, 2025
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Using Microwave and Macroscopic Samples of Dielectric Solids to Study the Photonic Properties of Disordered Photonic Bandgap Materials
Published on: September 26, 2014
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Symmetry-enforced three-dimensional Dirac phononic crystals.
Xiangxi Cai1, Liping Ye1, Chunyin Qiu1
11Key Laboratory of Artificial Micro-Structures and Nano-Structures of Ministry of Education and School of Physics and Technology, Wuhan University, 430072 Wuhan, China.
Light, Science & Applications
|March 21, 2020
Summary
Researchers experimentally observed symmetry-enforced Dirac points in a 3D phononic crystal. This novel material hosts unique topological surface states with potential for acoustic applications.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Acoustics
Background:
- Dirac semimetals are critical states in topologically distinct phases, characterized by fourfold degenerate Dirac points.
- Typically, Dirac points are created via band inversion and can be annihilated by perturbations without altering system symmetry.
Purpose of the Study:
- To experimentally observe symmetry-enforced Dirac points in a novel material system.
- To investigate the topological properties and surface states of this new Dirac system.
Main Methods:
- Fabrication and characterization of a nonsymmorphic three-dimensional phononic crystal.
- Experimental observation of Dirac points enforced by crystal symmetry.
- Surface measurements to confirm topological surface states.
Main Results:
- Experimental confirmation of symmetry-enforced Dirac points in the phononic crystal.
- Observation of four spiral topological surface states.
- Gapless intersection of surface states with opposite helicities along specific momentum lines.
Conclusions:
- The developed phononic crystal provides a unique platform for studying symmetry-enforced Dirac points.
- The system exhibits novel topological surface states with potential applications in acoustics.
- This work opens new avenues for exploring elusive topological phenomena.
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