Direct Near-Field Optical Imaging of Higher Order Plasmonic Resonances

• DOI: 10.1021/nl801396r
• Publication Date: 2008-09-13T09:01:36Z
• Authors: R. Esteban; R. Vogelgesang; J. Dorfmüller; A. Dmitriev; C. Rockstuhl; C. Etrich; K. Kern
• Keywords: Colloidal Lithography; Microscopy; Optics and Photonics; Surface Properties; Physics; ddc:530; Equipment Design; 02 engineering and technology; Contrast; Microscopy, Scanning Probe; Surface Plasmon Resonance; Probe; 530; Nanostructures; Microscopy, Electron; Metamaterials; Modes; Nanoparticles; Nanotechnology; Resolution; info:eu-repo/classification/ddc/530; 0210 nano-technology; Simulation

We map in real space and by purely optical means near-field optical information of localized surface plasmon polariton (LSPP) resonances excited in nanoscopic particles. We demonstrate that careful polarization control enables apertureless scanning near-field optical microscopy (aSNOM) to image dipolar and quadrupolar LSPPs of the bare sample with high fidelity in both amplitude and phase. This establishes a routine method for in situ optical microscopy of plasmonic and other resonant structures under ambient conditions.