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Electronic Raman scattering in metallic carbon nanotubes Mildred S. Dresselhaus, Massachusetts Institute of Technology, DMR 0704197.
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Electronic Raman scattering in metallic carbon nanotubesMildred S. Dresselhaus, Massachusetts Institute of Technology, DMR 0704197 Raman scattering is widely used for characterizing nanostructured graphitic materials such as carbon nanotubes, and graphene. To date, Raman studies on carbon materials have focused on light scattering by vibrational excitations (phonons). We have observed a new spectral feature in the Raman spectra of metallic carbon nanotubes associated with electronic Raman scattering (ERS) processes. Low energy electron-hole pairs inelastically scatter light due to the Coulomb interaction. This fundamental and interesting effect provides an optical method for probing the low energy electronic excitations of metallic nanotubes. Tangential phonon modes Radial breathing phonon mode Electronic Raman Scattering e-h pair The Raman spectrum of an isolated metallic single wall carbon nanotube. The shaded area represents the newly observed feature ERS associated with light scattering by electron-hole pairs.