Arrays of wirelike microstructures of Ag with visible wavelength transparent plasmonic response at near-ultraviolet and midinfrared regions

摘要

We present a simple masked thermal evaporation technique to fabricate arrays of wirelike Ag microstructures of width 8 mum with an extremely high aspect ratio on either silicon or glass substrates. In accordance with the theory of periodic arrays of thin wires, the electromagnetic response of Ag microstructures has shown a characteristic low-frequency plasmonic behavior with a transparent visible region. Plasmon absorption is observed to be splitted largely into transverse and predominating longitudinal bands at near-ultraviolet (415 nm) and midinfrared wavelengths (2867 nm), corresponding to the oscillation of the free electrons perpendicular to and along the long axis of the wires. (C) 2004 American Institute of Physics.