Background-free imaging of plasmonic structures with cross-polarized apertureless scanning near-field optical microscopy

• Published in: Review Of Scientific Instruments, vol. 83, p. -
• Publication date: 2012

We present advances in experimental techniques of apertureless scanning near-field optical microscopy (aSNOM). The rational alignment procedure we outline is based upon a phase singularity that occurs while scanning polarizers around the nominal cross-polarized configuration of s-polarized excitation and p-polarized detection. We discuss the theoretical origin of this topological feature of the setup, which is robust against small deviations, such as minor tip misalignment or shape variations. Setting the polarizers to this singular configuration point eliminates all background signal, allowing for reproducible plasmonic eigenmode mapping with optimal signal-to-noise ratio. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.3693346]

Keywords: Nanostructures ; Resonances ; Contrast ; Probe ; Nanocavities ; Resolution ; Amplitude ; Model

Reference

• EPFL-ARTICLE-176778
• doi:10.1063/1.3693346
• View record in Web of Science

Record created on 2012-05-04, modified on 2017-05-12