Ultraviolet plasmon resonance in transition-metal doped aluminum nanoparticle arrays

An ordered arrangement of metal nanoparticles is an ideal platform for extreme light localization, thanks to the optically driven free electrons that couple electrically across the interparticle gap region. In this work, we use time-dependent density functional theory calculations to investigate the optical response modulations in impurity (Fe/Co/Ni) doped planar square-shaped aluminum nanoparticle arrays by varying the interparticle gap distances in the range of 1 to 3 nm. The spectral maximum of the enhancement emerges in the near-ultraviolet region for the Fe-doped aluminum nanoparticle array for an interparticle gap distance of 1 nm. Increasing the interparticle gap distances to 2 and 3 nm causes a significant reduction in the spectral intensities as a consequence of decreased interaction among the nanoparticles. This finding shows that transition-metal impurities can provide a potential mechanism for manipulating the spectral response of the aluminum nanoparticle arrays, which may find applications in aluminum plasmon-mediated photocatalysis.