DNA Plasmon

As a consequence of the charged nature of a dissolved DNA polymer and its sheath of counterions we predict that there should exist normal modes of the system characterized by substantial longitudinal electric fields and relatively small motion of the atoms and ions. This longitudinal phonon is the one-dimensional counterpart of the plasmon excitation of three-dimensional conductors, and of the surface plasmon of two-dimensional charged systems. The frequency of the DNA plasmon, as a function of excitation wavelength, is linear in inverse wavelength at long wavelengths.