High-Resolution Imaging and Spectroscopy of Multipolar Plasmonic Resonances in Aluminum Nanoantennas

TitleHigh-Resolution Imaging and Spectroscopy of Multipolar Plasmonic Resonances in Aluminum Nanoantennas
Publication TypeJournal Article
Year of Publication2014
AuthorsMartin, J, Kociak, M, Mahfoud, Z, Proust, J, Gerard, D, Plain, J
JournalNANO LETTERS
Volume14
Pagination5517-5523
Date PublishedOCT
ISSN1530-6984
Abstract

We report on the high resolution imaging of multipolar plasmonic resonances in aluminum nanoantennas using electron energy loss spectroscopy (EELS). Plasmonic resonances ranging from near-infrared to ultraviolet (UV) are measured. The spatial distributions of the multipolar resonant modes are mapped and their energy dispersion is retrieved. The losses in the aluminum antennas are studied through the full width at half-maximum of the resonances, unveiling the weight of both interband and radiative damping mechanisms of the different multipolar resonances. In the blue-UV spectral range, high order resonant modes present a quality factor up to 8, two times higher than low order resonant modes at the same energy. This study demonstrates that near-infrared to ultraviolet tunable multipolar plasmonic resonances in aluminum nanoantennas with relatively high quality factors can be engineered. Aluminum nanoantennas are thus an appealing alternative to gold or silver ones in the visible and can be efficiently used for UV plasmonics.

DOI10.1021/nl501850m