Transformation of intensities and phases of light beams by a transient "undisplaced" holographic grating

A description is given of a mechanism of the transient transformation of energies and phases of light beams in recording of dynamic holographic gratings in weakly absorbing media. Simultaneous solution of a nonlinear system of permittivity and Maxwell equations for the transient case gives the parameters of the transformation of light beams used in the recording of such holographic gratings. The calculated parameters of energy exchange are compared with the experimental data for thermal holographic gratings in a solution of cryptocyanine.