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arXiv · 1402.7128

Electron spin-orbit interaction in helically coiled carbon nanotube

Ning Ma·Daqing Liu·Vei Wang·Erhu Zhang·Shengli Zhang
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Abstract

Recent theoretical and experimental works on carbon nanotubes (CNTs) have revealed that spin-orbit interaction (SOI) is more robust than it was thought. Motivated by this, we investigate the SOI in helically coiled CNTs. Calculations are performed within the tight-binding model with the inclusion of a four-orbital basis set; thereby the full symmetry of the helical lattice and the hybridization of $\pi $\ and $\sigma $ bands are considered. By virtue of unitary transformation and perturbation approach, we obtain the analytic solution for the torsion-dependent SOI in helically coiled CNTs. Due to the enhancement of curvature and torsion, the calculated SOI values reach the order of meV which has been confirmed by \textit{ab initio} electronic structure calculation.

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Ning Ma, Daqing Liu, Vei Wang, Erhu Zhang, Shengli Zhang. 2014-02-28. Electron spin-orbit interaction in helically coiled carbon nanotube. https://arxiv.org/abs/1402.7128

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