Abstract

Several techniques for determination of grating phase shifts relative to intensity grating have been developed by introducing artificial phase mismatch which includes by moving the nonlinear material, by phase shifting one of the two writing beams or by applying external electric fields.⁽¹⁾ In this work, we performed two kinds of experiment for two-wave energy couplings in a photopolymer film: (i) measurement of grating phase shifts of phase grating (PG) and absorption gratings (AG) by translation of the material along the grating wave vector K, (ii) experimental observation of quasi-periodic dynamic self-diffraction oscillations without introducing artificial phase mismatch.

© 1998 IEEE