局部表面共振对传输和分散增强的影响

We investigate the enhanced transmission through the square array of metallic coaxial annular apertures (MCAAs) in microwave

frequency by varying the inner diameter of the apertures. The impact of local resonance is thoroughly embodied in the even-mode

surface resonances, while the odd-mode surface resonances, invisible in measurements, are only scaled by periodicity. For MCAAs

with smaller inner diameters, the transmission extrema are measured at specific incident angles matching the folded degenerate

resonant states. The results are well understood in terms of the dispersion of surface resonances.