Weakly multimode dynamics of a photorefractive oscillator

D. Hennequin, L. Dambly, D. Dangoisse, P. Glorieux

J. Phys. III France 4 2459-2469 (1994)

The dynamics of a photorefractive oscillator has been studied in the weakly multimode case. It is shown that the eigenmodes of the empty cavity provide the bases in which the transverse patterns of this oscillator should be analysed. The concept of mode families i.e. sets of frequency degenerate modes, is very efficient to classify the different ranges of operation of the oscillator with Fresnel number up to 5-7. As the complexity of the patterns increases, the interpretation in terms of optical defects or phase singularities greatly simplifies the analysis.