Metamaterial grounded planar bilayers supporting leaky waves: principles and applications

In this contribution, we review the analysis of metamaterial grounded planar bilayers supporting leaky-waves, which we have recently proposed elsewhere as compact sub-wavelength leaky-wave radiators, and for enhancing the wave transmission through apertures over conducting screens when used as covers. Exploiting the peculiar resonances arising when »complementary« or »conjugate« metamaterials are paired, together with the focusing properties of low-permittivity and/or low-permeability materials, it is possible to operate a sub-wavelength open waveguide consisting of a stack of grounded metamaterial bilayers in the leaky-wave regime. We recall the salient guidance and radiation properties of these anomalous natural modes, providing some physical insights into the phenomenon and speculating on the connections between these two potential applications.