Gyrotropy and absorption of DNA and amylose at THz frequencies

Permittivity tensor of an ensemble of equal double stranded DNA molecules in the terahertz frequency range was qualitatively analyzed within the self-consistent phonon approximation. The model showed the dependence of the tensor components on such parameters as DNA length and helix period. The corresponding DNA absorption spectra were calculated. It is shown specifically that a localization of the absorption lines in the THz frequency range is determined by the DNA helix structure whereas the DNA length is responsible for a separation between the absorption lines.