Near-field optical microscopy and spectroscopy with pointed probes
Lukas Novotny1, Stephan J Stranick
1The Institute of Optics, University of Rochester, Rochester, New York 14627, USA. novotny@optics.rochester.edu
Annual Review of Physical Chemistry
|April 8, 2006
Summary
Apertureless near-field techniques enable nanoscale chemical and material analysis using spectroscopic contrast. This review covers advancements in pointed probe microscopy for sub-100 nm imaging.
Area of Science:
- Optics and Photonics
- Nanotechnology
- Spectroscopy
Background:
- Near-field optical microscopy traditionally used aperture-based probes.
- Apertureless techniques offer enhanced capabilities for nanoscale analysis.
- Spectroscopic contrast mechanisms are crucial for detailed material characterization.
Purpose of the Study:
- To review the evolution of near-field optical microscopy.
- To highlight advancements in apertureless probe techniques.
- To discuss theoretical and experimental progress in the field.
Main Methods:
- Exploitation of far-field illumination with pointed, apertureless probes.
- Implementation of spectroscopic contrast mechanisms (Raman, IR absorption).
- Utilizing dielectric dispersion for materials contrast.
Main Results:
- Apertureless techniques enable spectroscopic contrast at sub-100 nm scales.
- Advances in theoretical descriptions of probe-field interactions.
- Progress in experimental scattering and excitation probe techniques.
Conclusions:
- Apertureless near-field microscopy is a rapidly advancing field.
- These techniques provide powerful tools for nanoscale chemical and materials science.
- Further theoretical and experimental developments are expected.
Related Concept Videos
01:22Overview of Microscopy Techniques
The early pioneers of microscopy opened a window into the invisible world of microorganisms. In 1830, Joseph Jackson Lister created an essentially modern light microscope. The 20th century saw the development of microscopes that leveraged nonvisible light, such as fluorescence microscopy that uses an ultraviolet light source and electron microscopy that uses short-wavelength electron beams. These advances significantly improved magnification, image resolution, and contrast. By comparison, the...
01:16Confocal Fluorescence Microscopy
Confocal microscopy is an advanced microscopic technique. The prime advantage of the confocal microscope over other microscopy techniques is its ability to block the out-of-focus light from the illuminated samples using pinholes. It is widely used with fluorescence optics to obtain high-resolution, sharp contrast images. Unlike optical microscopes, confocal microscopes use a focused beam of light laser to scan the entire sample surface at different z-planes. These microscopes are, therefore,...
01:37Super-resolution Fluorescence Microscopy
Super-resolution fluorescence microscopy (SRFM) provides a better resolution than conventional fluorescence microscopy by reducing the point spread function (PSF). PSF is the light intensity distribution from a point that causes it to appear blurred. Due to PSF, each fluorescing point appears bigger than its actual size, and it is the PSF interference of nearby fluorophores that causes the blurred image. Various approaches to achieving higher resolution through SRFM have recently been developed.