Localized Surface Plasmon Resonance of Metal Nanodot Nanowire Arrays Studied by Far-Field and Near-Field Optical

Abstract : A combination of AFM nanomachining and lift-off process based on the one-layer approach is a convenient method for the fabrication of metal nanostructures. For an obtained Au nanodot array with an average diameter of 72 nm, the resonance peak in the LSPR scattering spectrum is located at 548 nm and consistent with simulated spectrum from Mie theory. For the Au nanowire arrays, the LSPR scattering spectra are composed of two resonance peaks in the red and the blue regions. The two peaks can be attributed to resonances along the width and the thickness directions. It is found that the red peak experiences a red shift when the width increases, whereas the blue peak experiences a blue shift when the thickness increases. However, both peaks experience a red shift when the aspect ratio of width to thickness increases. Furthermore, a linear behavior is observed in all the relationships. Additionally, a propagating length of around 10 ?m is observed for the SPPs at a wavelength of 532 nm in an Au stripe.