Scanning near-field optical nanotomography: a new method of multiparametric 3D investigation of nanostructural materials

A new experimental approach to multiparametric three-dimensional (3D) investigation of a broad class of composite nanostructural materials is developed on the basis of scanning near-field optical nanotomography (SNONT). Using this method, it is possible to simultaneously study the optical properties, 3D morphology, and distribution of the mechanical and electrical properties of the same region of a sample. The proposed method combines features of the confocal and near-field optical microspectroscopy (fluorescence and Raman spectroscopy) with a lateral resolution of up to 50 nm and scanning-probe microscopy. The possibility of studying the volume distribution of optical, morphological, electrical, and mechanical characteristics of a material with nanoscale resolution is related to the probing of sequential layers at a step of up to 20 nm and a total Z-scan depth of up to 3 mm. In particular, the SNONT method has been used to study a liquid-crystalline polymer doped with fluorescent nanocrystals.