We examine the optical properties of metals containing a periodic arrangement
of nonoverlapping spherical mesopores, empty or filled with a dielectric
material. We show that a slab of such a porous metal transmits light over
regions of frequency determined by the dielectric constant of the cavities and
the fractional volume occupied by them, with an efficiency which is many orders
of magnitude higher than predicted by standard aperture theory. Also, the
system absorbs light efficiently over the said regions of frequency unlike the
homogeneous metal.Comment: 9 pages in total, 3 figures To be published in Solid State
Communication
