The basic idea is that the structure we designed and made:
can spectrally and spatially split incoming radiation into different holes in the metal, where it is almost entirely absorbed. This is pseudo-color plot (from a simulation) of where the absorption happens inside a single unit cell of the structure:
For the rest of the info, read the paper!
E. Lansey, et al., "Light localization, photon sorting, and enhanced absorption in subwavelength cavityarrays," Opt. Express 20, 24226-24236 (2012).