Direct Observation of Plasmonic Modes in Au Nanowires Using High-Resolution Cathodoluminescence Spectroscopy

• Published in: Nano letters Vol. 7; no. 9; pp. 2843 - 2846
• Main Authors: Vesseur, Ernst Jan R, de Waele, René, Kuttge, Martin, Polman, Albert
• Format: Journal Article
• Language: English
• Published: Washington, DC American Chemical Society 01.09.2007
• Subjects: Collective excitations (including excitons, polarons, plasmons and other charge-density excitations); Condensed matter: electronic structure, electrical, magnetic, and optical properties; Cross-disciplinary physics: materials science; rheology; Electrodes; Electronic structure and electrical properties of surfaces, interfaces, thin films and low-dimensional structures; Exact sciences and technology; Gold - chemistry; Luminescent Measurements - methods; Materials science; Materials Testing; Nanocrystalline materials; Nanoscale materials and structures: fabrication and characterization; Nanotechnology - methods; Nanotubes - chemistry; Particle Size; Physics; Reproducibility of Results; Sensitivity and Specificity; Spectrum Analysis - methods; Surface and interface electron states; Surface Plasmon Resonance - methods; Gold; Dispersion relations; Imaging; Plasmons; Nanowires; Cathodoluminescence; Nanostructured materials
• ISSN: 1530-6984; 1530-6992
• DOI: 10.1021/nl071480w

We use cathodoluminescence imaging spectroscopy to excite and investigate plasmonic eigenmodes of Au nanowires with lengths of 500−1200 nm and ∼100 nm width. We observe emission patterns along the Au nanowire axis that are symmetric and strongly wavelength dependent. Different patterns correspond to different resonant modes of the nanowire. From the observed patterns, we derive the spatial and spectral properties of the wire eigenmodes and determine the dispersion relation for plasmonic Au nanowire modes.