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Updated: Jul 2, 2025
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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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Acoustic Higher-Order Topological Insulators Induced by Orbital-Interactions
Feng Gao1, Yu-Gui Peng1, Xiao Xiang1
1School of Physics and Innovation Institute, Huazhong University of Science and Technology, Wuhan, 430074, China.
Advanced Materials (Deerfield Beach, Fla.)
|February 22, 2024
Summary
This study demonstrates novel higher-order topological acoustic states using degenerate orbitals. These orbital-selective corner and edge states offer new possibilities for acoustic sensing and trapping applications.
Area of Science:
- Acoustic metamaterials
- Topological physics
- Condensed matter theory
Background:
- Higher-order topological insulators (HOTIs) are analogous to condensed-matter systems.
- Pseudo-spins are commonly used to induce topological phenomena in HOTIs.
- Previous Type-II corner states relied on long-range hoppings in single-orbital systems.
Purpose of the Study:
- To demonstrate versatile, orbital-selective, higher-order topological corner states in acoustic resonant cavities.
- To investigate Type-II corner states without long-range hoppings.
- To realize orbital-dependent edge modes using degenerate p orbitals.
Main Methods:
- Exploiting degenerate orbitals in acoustic resonant cavities.
- Tailoring orbital interactions to induce Type-II corner states.
- Utilizing the orthogonal nature of p orbitals for edge mode realization.
Main Results:
- Demonstration of orbital-selective, higher-order topological corner states.
- Experimental validation of Type-II corner states without long-range hoppings.
- Observation of orbital-dependent edge modes with high-Q factors within bulk bands.
Conclusions:
- Acoustic orbitals and topology interplay is elucidated.
- A universal strategy for orbital-dependent topological edge modes is introduced.
- Findings pave the way for advanced acoustic sensing and trapping technologies.
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