title: Comparison of the sensitivity and image contrast in spontaneous Raman and coherent Stokes Raman scattering microscopy of geometry-controlled samples.
abstract: We experimentally compare the performance and image contrast of spontaneous Raman and coherent Stokes Raman scattering microscopy. We demonstrate the differences between these techniques on a series of geometry-controlled samples that range in complexity from a point (array of tips) to one-dimensional (line grating) and, lastly, two-dimensional (checkereboard) microstructure. Through the use of this sample series, a comparison of the focal volume, achievable signal-to-noise, and resulting image contrast is made. The results demonstrate the efficiency and spatial resolution attainable in coherent Raman microscopy relative to spontaneous Raman microscopy. Additionally, we detail potential complications in the interpretation of coherent Raman images of sample fine structure, where contrast is no longer based solely on oscillator concentration but can be influenced by sample microstructure.
authors.affiliation: National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA.
authors.forename: Hyunmin
authors.initials: H
authors.lastname: Kim
authors.forename: Chris A
authors.initials: CA
authors.lastname: Michaels
authors.forename: Garnett W
authors.initials: GW
authors.lastname: Bryant
authors.forename: Stephan J
authors.initials: SJ
authors.lastname: Stranick
mesh_terms: D004867:Equipment Design; D019544:Equipment Failure Analysis; D007089:Image Enhancement / Q000379:methods*; D008853:Microscopy / Q000295:instrumentation*; D010363:Pattern Recognition, Automated / Q000379:methods*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013059:Spectrum Analysis, Raman / Q000295:instrumentation*