Localized Surface Plasmon Resonances in Aluminum Nanodisks

Department of Applied Physics, Chalmers University of Technology, 412 96 Göteborg, Sweden.
Nano Letters (Impact Factor: 13.59). 06/2008; 8(5):1461-71. DOI: 10.1021/nl080453i
Source: PubMed


The plasmonic properties of arrays of supported Al nanodisks, fabricated by hole-mask colloidal lithography (HCL), are analyzed for the disk diameter range 61-492 nm at a constant disk height of 20 nm. Strong and well-defined (UV-vis-NIR) localized surface plasmon resonances are found and experimentally characterized with respect to spectral peak positions, peak widths, total cross sections, and radiative and nonradiative decay channels. Theoretically, the plasmon excitations are described by electrostatic spheroid theory. Very good qualitative and quantitative agreement between model and experiment is found for all these observables by assuming a nanoparticle embedded in a few nanometer thick homogeneous (native) aluminum oxide shell. Other addressed aspects are: (i) the role of the strong interband transition in Al metal, located at 1.5 eV, for the plasmonic excitations of Al nanoparticles, (ii) the role of the native oxide layer, and (iii) the possibility of using the plasmon excitation as an ultrasensitive, remote, real-time probe for studies of oxidation/corrosion kinetics in metal nanoparticle systems.

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Available from: I. Zorić, Feb 25, 2015
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    • "Aluminum has a shorter skin depth than gold, meaning light can be confined very close to the antenna surface giving better optical resolution for imaging. Further to this, a thin layer of aluminum oxide forms on the aluminum surface, which protects the material underneath from further oxidation putting a protective barrier between the aluminum and its surroundings [30]. Different materials behave very differently during evaporative deposition and subsequent processing using FIB, which affects the overall resolution obtainable with the FIB system . "
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