Virtual Designer Metals for Enhancement of Plasmonic Nanoparticles Which Improve the Light Absorption in Silicon

Abstract Although it has been established that plasmonic nanostructures can enhance the optical absorption in thin‐film solar cells, despite Ohmic losses, more improvements are required to become interesting for applications. Here, virtual metals are improved by adjusting the refractive index with the particle swarm method to obtain virtual metal nanoparticles, which are optimized for optical absorption enhancement in silicon layers. The properties of these optimized virtual metals are investigated to determine the mechanism behind the plasmonic enhancement. Besides the plasmon resonance position and strength, the ability to position different orders of the plasmon resonance in the same wavelength range contributes to considerable improvements. The here obtained virtual metals can be a guide for developing new nanoscale alloys for solar cell plasmonics.