DNA-Wrapped Carbon Nanotubes as Potential Optoelectronic Materials

In the frame of tight-binding theory, we investigate modulation of the optical properties of single-wall carbon nanotubes (SWNTs) helically wrapped with single-stranded DNA. We predict that certain wraps may qualitatively change the one-electron absorption spectrum for light polarized across the SWNT. Lifting of the optical selection rules is due to nanotube symmetry-breaking in the Coulomb potential of the ionized DNA backbone.