Wave interactions in a left-handed mushroom structure

Metamaterials and, in particular, left-handed (LH) materials (negative refractive index metamaterials) have drawn considerable attention in the physics and engineering communities over the last five years. This paper presents a synthesis of the refractive characteristics of a mushroom structure, including dispersion diagram, fields distributions, isotropy and refractive index. In addition, it introduces and demonstrates the concept of plane wave to cylindrical wave transformation by way of a parabolically curved RH/LH interface. A practical mushroom implementation of this interface is also discussed.