Investigation of Leaky-Wave Propagation and Radiation in a Metal Cut-Wire Array

The leaky-wave propagation and radiation characteristics of a metal cut-wire array are studied. It is shown that a leaky-wave can exist in the structure at frequencies above the plasmonic cut-off. The field distribution, propagation and attenuation constants of the leaky-wave are extracted from simulation and measurement, and compared with the predictions based on a rigorous homogenization model. Next, directive radiation into the air region through the leaky-wave mechanism is explored. It is found that a directive, frequency scanned beam can be formed outside the cut-wire array. The phenomenon is demonstrated through theory, simulations and measurements.