Slow light and omnidirectional resonances in the metamaterial-based multi-layer structures

Metamaterials, with effective negative permittivity and/or negative permeability, have paid much attention in recent years. We present the results on slow light and omnidirectional resonances in the metamaterial-based structures. We have found that the group velocity vanishes in the planar and cylindrical waveguides consisting of the left-handed metamaterial core and the single-negative-permittivity cladding. Ultra-low group velocity dispersion has been also found in such waveguides. On the other hand, we have found out omnidirectional resonances in various kinds of 1D photonic crystal heterostructures possessing the zero-phi_eff/zero-nmacr gap, and in a simple sandwich structure. The mechanisms of both phenomena have been revealed, and the properties of them have also been studied.