Spencer, J. H., Nesbitt, J. M., Trewhitt, H., Kashtiban, R. J., Bell, G., Ivanov, V. G., Faulques, E., Sloan, J. & Smith, D. C. (2014) Raman Spectroscopy of Optical Transitions and Vibrational Energies of similar to 1 nm HgTe Extreme Nanowires within Single Walled Carbon Nanotubes. ACS Nano, 8 9044–9052.
Added by: Laurent Cournède (2016-03-10 21:01:55)
|Type de référence: Article
Numéro d'identification (ISBN etc.): 1936-0851
Clé BibTeX: Spencer2014
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Mots-clés: 1d, carbon nanotubes, confinement, crystals, dft, gap, HgTe@SWCNT, hrtem, nanowires, Phonons, resonant Raman spectroscopy, scattering, separation
Créateurs: Bell, Faulques, Ivanov, Kashtiban, Nesbitt, Sloan, Smith, Spencer, Trewhitt
Collection: ACS Nano
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This paper presents a resonance Raman spectroscopy study of similar to 1 nm diameter HgTe nanowires formed inside single walled carbon nanotubes by melt infiltration. Raman spectra have been measured for ensembles of bundled filled tubes, produced using tubes from two separate sources, for excitation photon energies in the ranges 3.39-2.61 and 1.82-1.26 eV for Raman shifts down to similar to 25 cm(-1). We also present HRTEM characterization of the tubes and the results of DFT calculations of the phonon and electronic dispersion relations, and the optical absorption spectrum based upon the observed structure of the HgTe nanowires. All of the evidence supports the hypothesis that the observed Raman features are not attributable to single walled carbon nanotubes, i.e., peaks due to radial breathing mode phonons, but are due to the HgTe nanowires. The observed additional features are due to four distinct phonons, with energies 47, 51, 94, and 115 cm(-1), respectively, plus their overtones and combinations. All of these modes have strong photon energy resonances that maximize at around 1.76 eV energy with respect to incident laser.
Added by: Laurent Cournède