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Raman spectra of BN-nanotubes: Ab-initio and bond-polarizability model calculations

Ludger Wirtz·Michele Lazzeri·Francesco Mauri·Angel Rubio
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Abstract

We present it ab-initio calculations of the non-resonant Raman spectra of zigzag and armchair BN nanotubes. In comparison, we implement a generalized bond-polarizability model where the parameters are extracted from first-principles calculations of the polarizability tensor of a BN sheet. For light-polarization along the tube-axis, the agreement between model and it ab-initio spectra is almost perfect. For perpendicular polarization, depolarization effects have to be included in the model in order to reproduce the it ab-initio Raman intensities.

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Ludger Wirtz, Michele Lazzeri, Francesco Mauri, Angel Rubio. 2005-04-14. Raman spectra of BN-nanotubes: Ab-initio and bond-polarizability model calculations. https://doi.org/10.1103/physrevb.71.241402

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