Raman Spectroscopy: Probing the Border Between Near-Field and Far-Field Spectroscopy
نویسندگان
چکیده
We have performed Raman spectroscopy using a near-field scanning optical microscope. The small sample volume coupled with the light-starved nature of the Raman effect makes nano-Raman studies difficult. We present results showing near-field effects in an investigation of Rb-doped KTP. These effects include a change in selection rules due to the presence of a z-polarization component in the near-field, a surface-enhancement effect in near-field Raman data, a reduced Rayleigh tail, and simultaneous topography with the near-field probe. An image taken within a Raman feature demonstrates that nanoRaman imaging is indeed possible if the near-field instrument has considerable long-term stability.
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