Broadband asymmetric transmission of optical waves from spiral plasmonic metamaterials

This study theoretically demonstrates a broadband circular asymmetric transmission effect on the basis of two dimensional planar spiral metamaterials. We found that by increasing the number of turns in a single spiral unit cell, the bandwidth of the asymmetric transmission effect will be broaden dramatically and reach to about 940 nm in the near-infrared spectral range. (C) 2014 AIP Publishing LLC.