Acoustic realization of quadrupole topological insulators
 
                   
                   
                        
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-   Journal:Physical Review Letters
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-   Abstract:A quadrupole topological insulator, being one higher-order topological insulator with nontrivial quadrupole quantization, has been intensely investigated very recently. However, the tight-binding model proposed for such emergent topological insulators demands both positive and negative hopping coefficients, which imposes an obstacle in practical realizations. Here we introduce a feasible approach to design the sign of hopping in acoustics, and construct the first acoustic quadrupole topological insulator that stringently emulates the tight-binding model. The inherent hierarchy quadrupole …
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-   Volume:124
-   Issue:20
-   Page Number:206601
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-   Translation or Not:no
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-   Date of Publication:2020-05-18
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-   Links to published journals:https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.124.206601