Effect of non-pore-widening on plasmon resonances of silver nanowire arrays in Anodized Aluminum Oxide

Surface plasmon excitation using resonant metal nanowires in Anodized Aluminum Oxide is studied experimentally. Absorption spectra measurement reveals the existence of broad-band plasmon resonances. Besides the regular resonances of ideal nanowire and plasmon coupling, effect of nanowire’s geometry is evident for absorption in irregular wavelength. This is ascribed to the pores without widening, resulting in not straight nanowires. Nanowire arrays with other diameters and interpore distances and Y-junction nanostructures are investigated to confirm this model. These findings are important for applications utilizing plasmon resonance of nanostructures.