We report on the optical characterization of semicontinuous nanostructured
silver films exhibiting tunable optical reflectance asymmetries. The films are
obtained using a multi-step process, where a nanocrystalline silver film is
first chemically deposited on a glass substrate and then subsequently coated
with additional silver via thermal vacuum-deposition. The resulting films
exhibit reflectance asymmetries whose dispersions may be tuned both in sign and
in magnitude, as well as a universal, tunable spectral crossover point. We
obtain a correlation between the optical response and charge transport in these
films, with the spectral crossover point indicating the onset of charge
percolation. Such broadband, dispersion-tunable asymmetric reflectors may find
uses in future light-harvesting systems.Comment: 18 pages, 5 figures, accepted by Journal of Applied Physic