Theoretical and experimental study of guided modes of the wire medium slab

We study the guided modes in the wire medium slab taking into account both the nonlocality and losses in the structure. We show that due to the fact that the wire medium is an extremeley spatially dispersive metamaterial, the effect of nonlocality plays a critical role since it results in coupling between the otherwise orthogonal guided modes. We show that such a structure supports a set of deep subwavelength propagating modes and that it exhibits properties of a single mode waveguide at any fixed frequency which is below the plasma frequency of the wires. We compare our analytical results with the dispersion relations extracted from the experimental measurements.