Study of Localized Surface Plasmon Resonance of Gold Nanodot and Nanowire Arrays

摘要

In recent years, extensive research activities are devoted to metal nanoparticles or nanostructures due to their applications as highly efficient chemical or biological sensors, nanophotonic devices, etc. This work utilizes atomic force microscopy nanolithography to fabricate gold nanodot and nanowire arrays on silicon substrates, and dark-field optical microscopy to investigate their localized surface plasmon resonance characteristics. For an obtained gold nanodot array, the average diameter is around 72 nm after thermal treatment, and the resonance peak in scattering spectrum is located at 548 nm. For the gold nanowire arrays, the thickness is 20 nm and the widths are ranging bptween 50 and 100 nm. The scattering spectra are composed of two resonance peaks in the blue and the red regions. It is also found that when the width is increased, the red peak experiences a red shift, whereas the blue peak remains unchanged. It is clear that the two peaks can be attributed to resonances along the thickness and width directions of the nanowires..