Inductive Meandered Metal Line Metamaterial for Rectangular Waveguide Linings

Metal-based epsilon negative metamaterials (MTMs) have been investigated for use as a waveguide liner to allow for an electromagnetic passband below the cutoff frequency of the empty waveguide. In this paper, we investigate both the theory and a practical implementation of an MTM lined waveguide. Specifically, we have investigated the use of inductive meander lines as the elements of a vacuum-electronics-compatible MTM structure to line one side of a rectangular waveguide. The MTM implementation creates an effective medium with a Drude-Lorentz dispersion response. The transmission of the waveguide and dispersion were both simulated and measured experimentally and demonstrate good agreement.