  The electronic Raman scattering (ERS) features of single-walled carbon
nanotubes (SWNTs) can reveal a wealth of information about their electronic
structures, but have previously been thought to appear exclusively in metallic
(M-) but not in semiconducting (S-) SWNTs. We report the experimental
observation of the ERS features with an accuracy of 1 meV in suspended S-SWNTs,
the processes of which are accomplished via the available high-energy
electron-hole pairs. The ERS features can facilitate further systematic studies
on the properties of SWNT, both metallic and semiconducting, with defined
chirality.
