@article{pacheco_barticevic_latgé_rocha_2006,  title={Optical properties of carbon nanotubes under external electric fields},  volume={36},  ISSN={0103-9733},  url={https://doi.org/10.1590/S0103-97332006000300056},  DOI={10.1590/S0103-97332006000300056},  number={2a},  journal={Brazilian Journal of Physics},  publisher={Sociedade Brasileira de Física},  author={Pacheco, M. and Barticevic, Z. and Latgé, A. and Rocha, C. G.},  year={2006},  month={Jun},  pages={440–442} }