Unlike conventional optics, scanning near-field optical microscopy (SNOM) overcomes the Rayleigh criterion and can therefore achieve better resolutions than conventional optical microscopes. This feature is utilized to measure the optical properties of different silver particle distributions on a glass surface. This paper mainly lays focus on intensity correction of the optical data due to topographical artifacts, analysis of plasmonic behavior and a tentative representation of the optical data.
The simple approach for optical artifact correction has been shown to yield qualitative success, with necessity of improvement for quantitative results. Given the conditions of the experiment, it has also been observed that plasmonic coupling seems to have a greater impact on the small observed particles. The tentative representation of the optics suggests that the larger particles are able to emit light by absorption of electromagnetic energy from their surrounding.
Contents
1 Introduction
2 Physical Principles
2.1 Near and Far Field
2.1.1 Limitation of Far-Field Measurement
2.1.2 Evanescent Wave Measurement via Slit
2.2 Evanescent Waves and Plasmons
2.3 Plasmon Resonance from Theory
2.4 SNOM Theory
2.4.1 Aperture-Mode
2.4.2 Shear Force Feedback
2.5 Topographic Artifacts
3 Setup
4 Samples
5 Experimental
5.1 Preparation of Measurement
5.2 Measurement Procedure
5.3 Calibration and Tip Properties
5.4 Results
6 Discussion
6.1 Optical Correction by Height
6.2 Correlation between Topography & Near-Field Optics
6.3 Analysis of Contractive Effects - Emission / Absorption
7 Summarizing Conclusion
8 Outlook
9 Appendices
9.1 Equipment
9.2 Program for Data Correction and Display
- Quote paper
- Steven Kämmer (Author), 2014, Characterisation of metallic particle distributions by scanning near-field optical microscopy (SNOM) in simultaneous reflection and transmission mode, Munich, GRIN Verlag, https://www.hausarbeiten.de/document/281073
