Edge states and corner modes in second-order topological phononic crystal plates

Amplitude-dependent topological edge states in nonlinear phononic lattices

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...

Complete phononic bandgaps and bandgap maps in two-dimensional silicon phononic crystal plates

It is shown that it is possible to obtain complete planar phononic bandgaps in square and hexagonal (honeycomb) lattice phononic crystals formed by etching a periodic array of circular holes in a thin silicon plate (or membrane). Also, better bandgap properties are obtained using the hexagonal lattice structure; and, with practical structure sizes, it is possible-to-obtain a gap-to-midgap ratio...

Helical edge states and topological phase transitions in phononic systems using bi-layered lattices

The slow zero order antisymmetric Lamb mode in phononic crystal plates.

In this paper, the group velocities of the zero order antisymmetric (A0) Lamb modes in a phononic crystal plate with single layer cylindrical holes parallel to the surface of the plate were investigated theoretically. The results show that by increasing the filling fraction, the A0 mode can be efficiently slowed down and the group velocity of the A0 modes can be tuned from the positive to the n...

Waveguiding in two-dimensional piezoelectric phononic crystal plates

We investigate the possibility of designing phononic crystal-based devices for telecommunication applications using materials commonly employed in microfabrication. We focus our attention on a phononic crystal made of a square array of cylindrical holes drilled in an active piezoelectric PZT5A matrix. Two different structures are considered, namely, a freestanding phononic crystal plate and a p...