Near field scanning optical with Raman microscopy

Jahncke, C.L., M.A. Paesler, and H.D. Hallen. 1995. Raman imaging with near-field scanning optical microscopy. Appl. Phys. Lett. 67 2483-2485. 

Scanning near-field optical microscopy is a technique that provides a way of circumventing the optical diffraction limit SNOM images with a spatial resolution of A/20 have been reported [27-33]. Because SNOM is an optical technique, it may be used to perform Raman spectroscopy with sub-A/2 spatial resolution [34-47]. 

The evolution of Raman instrumentation has been recently reviewed (Lewis, 2001a), from the first measurements by C.V. Raman, when the spectra were excited with a mercury lamp and recorded with a small prism spectroscope equipped with a photographic plate (Raman, 1928), to the new high resolution microscopes, in Raman scanning near-field optical microscopy (Adar, 2001). This review includes Raman microscopy (Baldwin, 2001), Raman imaging (Treado, 2001), the adaptation of Raman spectrometry to industrial environment (Slater, 2001), Raman spectroscopy of catalysts (Wachs, 2001) and process Raman spectroscopy (Lewis, 2001b). 

Near-field microscopy is another usefiil application of DUV plasmonics. In this method, scanning probe microscopy was combined with optical microscopy. A nano-sized probe was coated with plasmonic materials to localize the incident light at its apex. The spectroscopic signal was obtained primarily at the probe apex, realizing a nanoscale imaging resolution. Recently, near-field DUV Raman scattering with an aluminum tip has been reported with an enhancement factor of 1,300... 

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