Adding colors to polydimethylsiloxane by embedding vertical silicon nanowires

We demonstrate that embedding silicon nanowires into polydimethylsiloxane (PDMS) presents a means for adding color, i.e., provides filtering at visible and near-infrared wavelengths. Silicon nanowires are etched from a silicon wafer and transferred to a PDMS film. Each measured transmission spectrum exhibits a dip at a wavelength determined by the nanowire radius. This is in agreement with electromagnetic simulations, which also help elucidate the roles of scattering and absorption in the observed results.