Resonant Raman spectroscopy was performed to study electron-phonon coupling in single-walled carbon nanotubes separated in solution. By varying the excitation energy from 1.26 eV to 1.93 eV we obtained radial breathing mode resonance profiles of the first and second optical transitions E11 and E22 of the (9,1) and (8,3) tubes. We observe up to 16 times stronger Raman intensities for the E11 transitions which can mostly be attributed to a two times broader linewidth of the E22 transition. Comparison of the matrix element ratio 11/22 to theoretical predictions on the electron-phonon coupling show a deviation of a factor 1.7 which might be associated with the change of the exciton-photon matrix element.
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