Polarization-sensitive perfect plasmonic absorber for thin-film solar cell application

A polarization-sensitive perfect plasmonic absorber composed of three functional layers is designed and numerically investigated for harvesting of solar energy. The top layer is composed of plasmonic triangular nanoparticles made of aluminum, the middle layer is made of dielectric, and the bottom layer is composed of thick aluminum foil. The dimensions of the absorber structure are carefully selected to exhibit broadband absorption in the visible region, where the electromagnetic energy is maximum. Several configurations of the top layer containing triangular nanoparticles are analyzed with a special emphasis on broadband absorption. It is found that one of the types of absorber structure absorbs more than 90% of incoming light with large spectral width at various regions in the visible and near-infrared regions. Moreover, the weighted mean values under the AM1.5 solar spectrum are also calculated, and high values are obtained, which shows that the proposed structure is most appropriate for thin-film solar cells.