Generation of self-healing beams via four-wave mixing optical mode conversion

We present the experimental conversion of a spatially-Gaussian optical mode into a self-healing, approximate Bessel-Gauss mode by a non-collinear, spatially-multimode four-wave mixing process in warm atomic vapor. In addition to the mode conversion, a second, spatially-separate conjugate beam is created in a non-Gaussian mode that mimics that of the resulting converted probe beam. Additionally, we show that these resulting beams exhibit the ability to partially self-heal their mode profiles after encountering an obstacle in their paths. This multi-spatial-mode nonlinear gain platform may thus be used as a new method for all-optically generating pairs of self-healing beams.