Eur. Phys. J. B (2016) 89: 230
https://doi.org/10.1140/epjb/e2016-70476-8

Regular Article

Influence of strong screening effect on the perpendicular- polarized linear excitonic absorption spectra of semiconducting carbon nanotubes

¹ Physics Department of Nanjing Normal University, Nanjing 210023, P.R. China
² Department of Physics and CeOPP, University Paderborn, Warburger Str. 100, 33098 Paderborn, Germany

^a e-mail: 06183@njnu.edu.cn

Received: 10 August 2016
Published online: 24 October 2016

Abstract

For incident light polarized perpendicular to the tube axis the multi-band semiconductor Bloch equations (MB-SBEs) that involve various screened interband Coulomb interactions (ICIs) are derived. The calculated E₁₂ peak is very close to the longitudinal excitonic peak E₂₂. Compared with the previous theoretical peak positions, the blue-shift of the peak in our results is about 0.5 eV. Then, subsequent detailed analyses show that the screening effect on the diagonal ICIs (D-ICIs) plays a key role in this big blue-shift. The valley-degenerate transverse pair excitations holding the same selection rule further enhance the screening effect on D-ICIs. Specially at q = 0 the dielectric function acting on the D-ICIs enhances two times. In our calculation the strong screening effect contributes 90% of the big blue-shift, while the non-diagonal ICIs (ND-ICIs) contribute to 10% of the blue-shift.