Experimental characterisation of the bound acoustic surface modes supported by honeycomb and hexagonal hole arrays.

ABSTRACT: The Dirac point and associated linear dispersion exhibited in the band structure of bound (non-radiative) acoustic surface modes supported on a honeycomb array of holes is explored. An aluminium plate with a honeycomb lattice of periodic sub-wavelength perforations is characterised by local pressure field measurements above the sample surface to obtain the full band-structure of bound modes. The local pressure fields of the bound modes at the K and M symmetry points are imaged, and the losses at frequencies near the Dirac frequency are shown to increase monotonically as the mode travels through the K point at the Dirac frequency on the honeycomb lattice. Results are contrasted with those from a simple hexagonal array of similar holes, and both experimentally obtained dispersion relations a

SUBMITTER: Starkey TA 

PROVIDER: S-EPMC6823496 | biostudies-literature | 2019 Oct

REPOSITORIES: biostudies-literature