At least some aspects of the present disclosure feature a waveguide for propagating an electromagnetic wave. The waveguide includes a base material and a plurality of resonators disposed in a pattern, the plurality of resonators having a resonance frequency. Each of the plurality of resonators has a relative permittivity greater than a relative permittivity of the base material. At least two of the plurality of resonators are spaced according to a lattice constant that defines a distance between a center of a first one of the resonators and a center of a neighboring second one of the resonators.