J. Raman Spectroscopy, 27, 579-586 (1996) Invited Contribution to JOURNAL OF RAMAN SPECTROSCOPY "RAMAN MICROSCOPY AND IMAGING" Nano-Raman Spectroscopy and Imaging with the Near-field Scanning Optical Microscope 1 C.L. Jahncke, H.D. Hallen, and *M.A. Paesler Physics Department, North Carolina State University Raleigh, NC 27695-8202 Abstract We have performed Raman spectroscopy using a near-field scanning optical microscope. This avoids the diffraction limit inherent with conventional optical microscopy techniques involving far-field optical components, and allows volumes significantly smaller than the cube of the wavelength to be investigated. The small sample volume coupled with the light-starved nature of the Raman effect itself makes such nano-Raman studies difficult. We describe a near-field Raman microscope and present results showing near-field effects in an investigation of Rb-doped KTP. An image taken within a Raman feature demonstrates that nano-Raman imaging is indeed possible if the near-field instrument has considerable long- term stability, and that several unique aspects of the near field data recommend this approach. I. Introduction Optical microscopy and Raman spectroscopy are proven analytical tools that have been successfully coupled in micro-Raman studies that span a broad range of materials and applications. By their very natures, however, the two techniques each independently contribute to severe restrictions in the amount of light available for analysis and imaging. Microscopy gathers light from a restricted sample volume, and Raman spectroscopy involves use of a restricted spectral band of light involving an effect with relatively low quantum efficiency. The consequent light-starved nature of micro-Raman spectroscopy can make advances toward finer spatial or spectral resolution difficult. 1 Current address: Physics Department, St. Lawrence University, Canton, NY 13617