A recipe for making materials with negative refraction in acoustics
arXiv:0710.5221 · doi:10.1016/j.physleta.2007.11.037
Abstract
A recipe is given for making materials with negative refraction in acoustics, i.e., materials in which the group velocity is directed opposite to the phase velocity. The recipe consists of injecting many small particles into a bounded domain, filled with a material whose refraction coefficient is known. The number of small particles to be injected per unit volume around any point is calculated as well as the boundary impedances of the embedded particles.