AN ANALYTICAL SOLUTION FOR LARGE MODULATION EFFECTS IN PHOTOREFRACTIVE 2-WAVE COUPLINGS

An alternative empirical correction function is presented for the space-charge field of the form f(m) = m/(1+bm), which simulates the functional form of f(m) = [1-exp(-am)]/a, introduced by Refregier et al. [J. Appl. Phys. 58 (1985) 45]. A simple analytical solution describing the large modulation effects in photorefractive two-wave couplings is found and compared with the experimental results of BaTiO3 crystal, which shows good agreement with the theory for the whole range of modulation m.