All-optical synthetic spin-Hall effect in third-order nonlinear optics

We present experimental evidence of a synthetic spin -Hall effect in an all-optical third-order nonlinear optical process via spatial symmetry-breaking in pseudo-spin textures created by a spatially structured pump laser beam. The experimental configuration consists of a moderately focused pump laser beam undergoing a parametric interaction with an organic solvent (toluene), and an off-resonant laser beam probes the non-trivial spatial magnetization textures created by the pump beam. The phase profile of the transmitted probe beam is extracted using phase retrieval algorithms for ascertaining the analogous-spin states, which is shown to be consistent with the estimation of Berry’s phase that we obtain via paraxial approximation-based modeling of third-order nonlinear interaction.