Quantitative Imaging of Rapidly Decaying Evanescent Fields Using Plasmonic Near-Field Scanning Optical Microscopy

• DOI: 10.1038/srep02803
• Publication Date: 2013-09-30T09:03:07Z
• Authors: Zhen Zhang; Phillip Ahn; Biqin Dong; Oluwaseyi Balogun; Cheng Sun
• Keywords: Superlens

Non-propagating evanescent fields play an important role in the development of nano-photonic devices. While detecting far-field can be accomplished by coupling it to propagating waves, practice they are measured presence unwanted background components. It leads a poor signal-to-noise ratio and thus errors quantitative analysis local fields. Here we report on plasmonic near-field scanning optical microscopy (p-NSOM) technique that incorporates nanofocusing probe for adiabatic focusing surface plasmon polaritons at apex enhanced waves far-field. In addition, harmonic demodulation is employed suppress contribution background. Our experimental results show strong evidence free imaging using new p-NSOM technique. Furthermore, present measurements cavity modes quantify their contributing sources analytical model.