High-Resolution Near-Field Raman Microscopy of Single-Walled Carbon Nanotubes

We present near-field Raman spectroscopy and imaging of single isolated single-walled carbon nanotubes with a spatial resolution of $\approx 25\mathrm{n}\mathrm{m}$. The near-field origin of the image contrast is confirmed by the measured dependence of the Raman scattering signal on tip-sample distance and the unique polarization properties. The method is used to study local variations in the Raman spectrum along a single single-walled carbon nanotube.