Topological interface states by energy hopping within power-law variable section waveguides

Abstract

An energy-hopping one-dimensional acoustical topology within power-law variable section waveguides is proposed in this paper, wherein a topological phase transition results from the energy in the basic unit hopping to the nearby unit, with the same energy mode causing its energy band to first close and then open. This study can achieve improved sound energy at the topological interface state and further regulate sound energy based on enhanced sound energy. The large open hole determines the wide frequency range where the designable topological interface state is constructed and the power law of the curve of the structure can adjust the size of the common forbidden band of the two topological states to further improve the bandwidth. The small open hole regulates the magnitude of the acoustic energy at the topological interface state. This research will provide guidance for designing acoustic devices with different frequencies and different acoustic energy concentrations and realizing engineering applications of other multifunctional acoustic devices.