Spiral-based phononic plates: From wave beaming to topological insulators

Abstract

Phononic crystals and metamaterials take advantage of pre-designed geometrical structures to sculpt elastic waves, controlling their dispersion using different mechanisms. These mechanisms revolve mostly around Bragg scattering (BS), local resonances (LR) and inertial amplification (IA), which employ ad-hoc, often problem-specific geometries. Here, we use parametrized, spiraling unit cells as building blocks for designing various types of phononic materials. We focus on planar spirals that are easy to fabricate, yet give rise to the desirable complex dynamics. By simple modifications of the spirals, we open full band gaps using BS, LR and IA. Moreover, we alter the underlying unit cell symmetry and lattice vectors, to create wave beaming and topologically protected band gaps, both affecting waves whose wavelength is much larger than the order of periodicity.

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Cited by in corpus (19)

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• Experimental demonstration of topological waveguiding in elastic plates with local resonators
• Architected lattices for simultaneous broadband attenuation of airborne sound and mechanical vibrations in all directions
• Nonlinear waves in flexible mechanical metamaterials
• Nanomechanical topological insulators with an auxiliary orbital degree of freedom
• Valley and pseudospin-valley topologically protected edge states in symmetric pillared phononic crystals
• Topological spin-Hall edge states of flexural wave in perforated metamaterial plates
• A flexible spiraling-metasurface as a versatile haptic interface
• Experimental Observation and Description of Bandgaps Opening in Chiral Phononic Crystals by Analogy with Thomson scattering
• Theory of Truncation Resonances in Continuum Rod-based Phononic Crystals with Generally Asymmetric Unit Cells
• Enhancement of deep-subwavelength band gaps in flat spiral-based phononic metasurfaces using the trampoline phenomena
• Polarization-dependent and Valley-protected Lamb Waves in Asymmetric Pillared Phononic Crystals
• Topological transition in spiral elastic valley metamaterials
• Odd elasticity and topological waves in active surfaces
• Transition fronts and their universality classes
• Harnessing curvature for helical wave generation in spiral-based metamaterial structures
• Pseudospin-valley-coupled phononic topological insulator with edge and corner states
• Topological defect states in elastic phononic plates