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Updated: Jan 8, 2026
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Experimental Methods for Spin- and Angle-Resolved Photoemission Spectroscopy Combined with Polarization-Variable Laser
Published on: June 28, 2018
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Twist-Induced All-Flat-Band Higher-Order Acoustic Topological Insulator
Min-Hang Ling1, Peng Wu1, Yu-Gui Peng1
1School of Physics and Innovation Institute, Huazhong University of Science and Technology, Wuhan, China.
Advanced Materials (Deerfield Beach, Fla.)
|December 24, 2025
Summary
Researchers developed a novel acoustic topological insulator using twisted Moiré superlattices (TMSs) with localized resonances. This design achieves all-flat-band topology, enabling edge, corner, and hinge states for advanced applications.
Area of Science:
- Acoustics
- Condensed Matter Physics
- Materials Science
Background:
- Twisted Moiré superlattices (TMSs) are known for unique periodicity and Bragg scattering, utilized in flat-band engineering.
- Achieving all-flat-band topology with intrinsic Moiré eigenmodes remains an underexplored area.
Purpose of the Study:
- To propose a novel acoustic flat-band higher-order topological insulator.
- To investigate the mechanism for achieving all-flat-band topology in acoustic Moiré superlattices.
Main Methods:
- Introduction of periodic strong localized resonances into Moiré superlattices.
- Utilizing the standing-wave effect of multipolar Mie resonances.
- Stacking acoustic TMS into a 3D configuration.
Main Results:
- Observation of varied-frequency edge states and high-quality (high-Q) corner states within topological all-flat-bandgaps.
- Demonstration of out-of-phase topological hinge states in a 3D configuration.
- Successful construction of an acoustic all-flat-band topological insulator.
Conclusions:
- A simple strategy for constructing acoustic all-flat-band topological insulators is presented.
- The proposed system offers potential for applications in energy harvesting and sensing.
- Localized resonances are key to achieving desired topological properties in acoustic Moiré systems.
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