3D sound wave focusing by 2D internal periodic structure of 3D external cuboid shape

[EN] In this work, we report the focusing effect of a 2D sonic crystal cuboid. The proposed sonic composite lens is vertically extended from a 2-D flat Phononic Crystal Structure, but it is found to be able to focus waves in a three-dimensional manner. By varying the cuboid size, beam dimensions change and transverse beam width values smaller than the classical diffraction limit (~0.3 of wavelength) can be obtained. Numerical results have been obtained by Finite Element Method.This work has been supported by RTI2018-100792-B-I00 (MICINN) and was partially carried out within the framework of the Tomsk Polytechnic University Competitiveness Enhancement Program. D. T.-S. acknowledges financial support from Ministerio de Ciencia, Innovación y Universidades de España through grant BES-2016-077133.Castiñeira Ibáñez, S.; Tarrazó-Serrano, D.; Candelas Valiente, P.; Minin, OV.; Rubio Michavila, C.; Minin, IV. (2019). 3D sound wave focusing by 2D internal periodic structure of 3D external cuboid shape. Results in Physics. 15:102582-1-102582-4. https://doi.org/10.1016/j.rinp.2019.102582102582-1102582-41