Finite-Frequency Topological Maxwell Modes in Mechanical Self-Dual Kagome Lattices

Abstract

In this Letter, an elastic twisted kagome lattice at a critical twist angle, called self-dual kagome lattice, is shown to exhibit peculiar finite-frequency topological modes which emerge when certain conditions are satisfied. These states are topologically reminiscent to the zero energy (floppy) modes of Maxwell lattices but they occur at a finite frequency in the band gap of self-dual kagome lattice. Thus, we present a completely new class of topological modes which share similarities with both the zero frequency floppy modes in Maxwell lattices and the finite energy in-gap modes in topological insulators. We envision the presented mathematical and numerical framework to be invaluable for many technological advances pertaining to wave phenomenon such as reconfigurable waveguide designs.

5 pages main article, 5 pages supplemental material

References in corpus (5)

• Classification of topological insulators and superconductors in three spatial dimensions
• Non-Hermitian chiral phononics through optomechanically-induced squeezing
• Existence of Corner Modes in Elastic Twisted Kagome Lattices
• Symmetry of the phonon landscape across the duality boundary of twisted kagomes lattices
• Topological Flexural Modes in Polarized Bilayer Lattices

Cited by in corpus (8)

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• Strain topological metamaterials
• Dynamics of self-dual kagome metamaterials and the emergence of fragile topology
• Fully-Polarized Topological Isostatic Metamaterials in Three Dimensions
• Omnidirectional domain wall modes protected by fragile topological states
• Edge States with Hidden Topology in Spinner Lattices
• 3D Topologically Polarized Elastic Metamaterials Enable Asymmetric Energy Isolation at Low Frequencies