Broadband antireflection and light-trapping enhancement of plasmonic solar cells

In this work, we demonstrate broadband extraordinary transmission and antireflection in two-dimensional periodic metallic cuboids at optical frequencies. These phenomena originate from nonresonant excitations of surface plasmons, and represent high antireflection simultaneously for a broad spectral band and a wide angular range of incidence with polarization insensitivity. Based on this principle, we further introduce such metallic cuboids arrays into silicon solar cells. It is shown that high performance of light trapping in the cells can be achieved with a significant enhancement of the ultimate quantum efficiency. This study shows promising applications of plasmonic nanostructures to high-efficiency photovoltaic devices.