Wide-Angle and Polarization-Insensitive Perfect Absorber for Organic Photovoltaic Layers

In this letter, we computationally explore a wide-angle and polarization-insensitive perfect absorber based on hybrid metal-dielectric-metal structures. By introducing an organic photovoltaic layer between top metallic nanopatterns and a continuous metal bottom plate, an enhanced angle-and polarization-insensitive absorption can be obtained in the spectral range 400-700 nm, which is promising to realize improved thin-film organic photovoltaic devices. The physical mechanism of the perfect absorber is explained theoretically and numerically by the critical coupling principle.