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Title: Enhancing Adaptable Topological Wave Bandwidth in Piezoelectric Metamaterials via Circuitry and Lattice Symmetry Control
Recently, an electromechanical metamaterial with integrated resonant circuit elements was developed that enables on-demand tailoring of the operating frequency and interface routes for topological wave transmission. However, limitations to the operating frequency region still exist, and a full exploration of the adaptive characteristics of the topological electromechanical metamaterial has yet to be undertaken. To advance the state of the art, this study investigates the ability to enhance the range of operating frequencies for topological wave transmission in a piezoelectric metamaterial by the reconfiguration of lattice symmetries and connection of negative capacitance circuitry. In addition, the capability to modify the interface mode localization is analyzed. The plane wave expansion method is utilized to define a working frequency region for protected topological wave transmission by evaluating a local topological charge. Numerical simulations verify the existence of topologically protected interface modes and illuminate how the localization and shape of these modes can be altered via external circuit parameters. Results show that the reconfiguration of the lattice structure and connection to negative capacitance circuity enhances the operating frequency bandwidth and interface mode localization control, greatly expanding the adaptive metamaterial capabilities.
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ASME 2020 Conference on Smart Materials, Adaptive Structures and Intelligent Systems
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National Science Foundation
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