Band structure and transmission of 3D chiral sonic crystals

Ruben Pico , Vicente Romero-García , Victor Sanchez-Morcillo , Alejandro Cebrecos , Lluis Miquel Garcia-Raffi

We study the properties of a novel type of sonic crystal formed by a periodic array of scatterers with spiral form. Such structures, previously introduced in photonics, present interesting properties related to the symmetry breaking induced by the chirality of its elements. It consists in a 3D periodic structure based on a local geometry that breaks the mirror symmetry with respect to its centre. The unit cell is composed by three elbow elements connecting all the dimensions in a loop: x-y, y-z and z-x. By periodic translation in the three main directions, the complete structure is generated leading to quasi-spirals arranged in a hexagonal distribution interlaced with different rotation phase. We investigate the phononic band structure of our crystal and the transmission spectrum with the Finite Element Method.

Mots clés: Sonic crystal; chirality; Band structure

Domaines: Acoustique [physics.class-ph]

Ruben Pico, Vicente Romero-García, Victor Sanchez-Morcillo, Alejandro Cebrecos, Lluis Miquel Garcia-Raffi. Band structure and transmission of 3D chiral sonic crystals. Acoustics 2012, Apr 2012, Nantes, France. ⟨hal-00811317⟩