Mitchell Institute for Fundamental Physics & Astronomy
College Station, Texas 77843
Essentially all fundamental processes take place in dimensions far beyond the diffraction limit of standard optical microscopy. Consequently, almost all spectroscopic information obtained so far is based on averaged data over many molecules. While we certainly can extract useful information of such experiments, there are fundamental constraints that would render a general single molecule, single catalytic site, or - presently a hot topic - single virus investigation with structural information desirable.
While optical super resolution methods based on fluorescence labelling exist and in many cases are already commercially available, this is not not generally applicable to other optical techniques. In such cases one has to utilize the so-called optical near field. I will address general aspects of near-field optics and in particular focus on the combination of near-field optics and Raman spectroscopy as a tool to investigate surfaces on the nanometer and potentially even smaller scales, particularly addressing the challenges when investigating minute sample amounts. Examples ranging from material science to bio-medical fields demonstrate the broad field of applications for such a technique.