NANO-RAMAN SPECTROSCOPY AND IMAGING WITH NEAR-FIELD SCANNING OPTICAL MICROSCOPE

Raman spectroscopy was performed using a near-field scanning optical m icroscope. This avoids the diffraction limit inherent in conventional optical microscopy techniques involving far-field optical components, and allows volumes significantly smaller than the cube of the waveleng th to be investigated. The small sample volume coupled with the light- starved nature of the Raman effect itself makes such nano-Raman studie s difficult. A near-held Raman microscope is described and results sho wing near-field effects in an investigation of Rb-doped KTP are presen ted. An image taken within a Raman feature demonstrates that nano-Rama n imaging is indeed possible if the near-field instrument has consider able long-term stability, and that several unique aspects of the near- field data recommend this approach.