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For thin-film solar cells, light absorption is usually proportional to the film thickness. However, if freely propagating sunlight can be transformed into a guided mode,[1] the optical path length significantly increases and results in enhanced light absorption within the cell.[2] We propose here a light absorber based on coupling from a periodic arrangement of resonant dielectric nanospheres. It is shown that whispering gallery modes in the spheres can be coupled into particular modes of the solar cell and significantly enhance its efficiency. We numerically demonstrate this enhancement using full-field finite difference time-domain (FDTD) simulations of a nanosphere array above a typical thin-film amorphous silicon (a-Si) solar cell structure. The in-coupling element in this design is advantageous over other schemes as it is composed of a lossless material, and its spherical symmetry naturally accepts large angles of incidence. Also, the array can be fabricated using simple, well-developed methods of self assembly and is easily scalable without the need for lithography or patterning. This concept can be easily extended to many other thin-film solar cell materials to enhance photocurrent and angular sensitivity. Thin-film photovoltaics offer the potential for a significant cost reduction [3] compared to traditional, or first generation, photovoltaics usually at the expense of high efficiency. This is achieved mainly by the use of amorphous or polycrystalline optoelectronic materials for the active region of the device, for example, a-Si. The resulting carrier collection efficiencies, operating voltages, and fill factors are typically lower than those for single-crystal cells …