Phononic crystals (PnC) are spatially periodic materials with band gaps that form by Bragg scattering of elastic waves. Within the frequency range a gap, wave propagation is not admitted. A long-standing limitation this class wavelength for band-gap formation must be on order unit-cell size. This restricts presence to relatively high frequencies given lattice spacing. Locally resonant metamater...

We investigate the performance of microwave-frequency phononic crystal resonators fabricated on thin-film lithium niobate for integration with superconducting quantum circuits. For different design geometries at millikelvin temperatures, we achieve mechanical internal quality factors Qi above 105–106 high microwave drive power, corresponding to 5×106 phonons inside resonator. By sweeping defect...

Abstract Uncertainties are unavoidable in practical engineering, and phononic crystals no exception. In this paper, the uncertainties treated as interval parameters, an crystal beam model is established. A perturbation-based finite element method (P-IFEM) affine-based (A-IFEM) proposed to study dynamic response of beam, based on which vibration transmission analysis can be easily implemented sa...

This work investigates the effect of nonlinearities on topologically protected edge states in one and two-dimensional phononic lattices. We first show that localized modes arise at the interface between two spring-mass chains that are inverted copies of each other. Explicit expressions derived for the frequencies of the localized modes guide the study of the effect of cubic nonlinearities on th...

Phononic crystals are resonant structures with great potential to be implemented in applications as liquid sensors. The use of the symmetry reduction technique allows introducing relevant transmission features inside bandgaps by creating defect modes in a periodic regular structure. These features can be used as measures to quantify changes in the speed of sound of liquid samples that could be ...

We investigate the harvesting of sound waves by exploiting a 3D-printed gradient-index phononic crystal lens. The concept is demonstrated numerically and experimentally for focusing audio frequency range acoustic in air to enhance energy harvesting. A finite-element model developed design unit cell dispersion properties construct 3D lens wave field simulations. Numerical simulations are present...