Broadband efficiency enhancement of solar cell by mixing metallic nanoparticles of different sizes

Near-field light enhancement of metallic nanoparticles has been used successfully in significant enhancement in solar cell efficiency. Due to a narrow wavelength range for a given particle size, efficiency is limited to a narrow range of spectra. Field concentration and decay from the particle surface is very sensitive to particle size. We discusses theoretically how a broader range can be covered up by mixing various size distributions in a proper fraction and absorption losses due the particle themselves could be minimized as well. Finally, we apply our model to a nanoisland silver film deposited with the help of Nd-YAG laser whose particle size distribution is obtained from AFM micrographs. Theoretically calculated near field enhancement is compared with transmission spectra of the film.