Dynamical-phase-modulated holography (DPMH)-a method for measuring hologram formation mechanisms and the nonlinear refractive index

The authors describe the features distinguishing phase-modulated holography from phase-intensitive experiments. Dynamical-phase-modulated holography is an extension of the theory of PMH in order to measure additionally relaxation time constants in a range limited only by the modulation technique of choice. Another extension of this method is a 4-beam technique with separate write and read-out beam pairs which allows the measurement of the nonlinear refractive index of absorbing as well as nonabsorbing, nonresonant materials with high sensitivity and moderate CW laser powers