Bessel light beam self-diffraction in heavily doped n-InP under conditions of high optical nolinearity

摘要

Self-diffraction of Bessel light beam in heavily doped n-InP has been experimentally studied. It is found that additional rings (diffracted orders) which have double structure appear in spatial spectrum of diffracted light. At certain conditions gaussian like central maximum can be also observed in spatial spectrum. Numerical simulations have been performed for the case of Raman-Nath regime and saturation nonlinearity. The results of simulations are in a good agreement with experimental data. The double structure of the diffraction rings can be explained in terms of the existence of forbidden directions for light diffraction.