Elastic Coiling-up-Space Metamaterial

Abstract

Coiling up space is a metamaterial technique that utilizes a subwavelength labyrinthine structure to achieve a high refractive index. Despite the various advances in acoustics, the coiling-up-space technique cannot be used in the elastic case owing to its tensor-based physics. In this study, we show that an elastic coiling up space is possible if the "fluidlike connection" and "isocurvature path" conditions are satisfied. These conditions overcome the tensorial nature of elastic waves and allow the change of displacement fields according to the geometry, as in the acoustic case with scalar fields. The proposed elastic coiling is and demonstrated.