The Inter-Strand Modes of the DNA as a Probe into MW-Radiation

We consider the regime in which the bands of the torsional acoustic (TA) and the hydrogen-bond-stretch (HBS) modes of the DNA interpenetrate each other. Within the framework of a model that accommodates the structure of the double helix, we find the three-wave interaction between the TA- and the HBS-modes, and show that microwave radiation could bring about torsional vibrations that could serve as a pump mode for maintaining the HBS-one. Rayleigh's threshold condition for the parametric resonance provides an estimate for the power density of the mw-field necessary for generating the HBS-mode.