Bortchagovsky E. Near-field microscopy and the use of functionalized tips

The thesis deals with the seeking of new approaches for scanning near-field optical microscopy. Beside of new concepts and the use of not yet accounted parameters of light, standard approaches were used too, namely, there was the search of conditions for the enhancement of local field and improvement of its localization. It was shown that it is possible by the use of asymmetric arrow-like shape of apertures. Also the mechanism of the creation of the field distribution over the aperture in a screen of finite thickness of a real metal was formulated. It is proposed to use ellipsometry-like registration in near-field optical microscopy what gives additional flexibility and has potential to distinguish contributions from topographical features of a surface and inclusions or other variation of local optical properties. One more new approach is the concept of remote probe what is the transfer of the area of the field localization by superlensing properties of a film of plasmonic metal. It is shown that this approach can have some advantage even in comparison to the situation with closer probe situated in the area of absent superlensing film. It was shown that the change of the local field can affect macroscopic parameters of registered light. The shape of the transmission spectra of thin films depends on substrates and at a resonance of film's material is described by Fano line instead of habitual Lorentz line, which appears only as a limiting case. Investigation of molecular layers by tip-enhancer Raman scattering allowed to propose the new concept of the Raman probe based on the functionalization, which enlarges the possibility of optical near-field microscopy for different not only optical effects. Beside of considered promising perspectives of this concept, such a functionalized tips can serve as an internal standard in tip-enhanced Raman scattering what is a first step in the transformation of this method to analytical one. Found in this work effects and interactions as well as proposed new concepts will allow to obtain new information and will open new avenue in the use of near-field optics for investigation both optical and non-optical effects with nanometer resolution using specific functionalized tips.