Experimental Demonstration of Stability of Symmetrically Tilted Optical Vortices

Vortices are a natural phenomenon that occur anywhere from stirring a cup of coffee to the atmospheres of other planets. Optical vortices are studied in laser beams with recent attempts to apply the physics of vortices in optical beams to vortices in quantum fluids. The Siemens group is interested in acquiring a particle description of vortices transposed into laser light to make connections between laser light and quantum fluids. Tilted vortices are a key component to this connection, so further investigation of their behavior is required. Higher charge tilted vortices split into unit charge vortices during free-space propagation, implying they are unstable and sensitive to perturbation. The Siemens group developed a theoretical model of generating symmetrically tilted vortices that do not split in the far-field. I experimentally verify this model by generating holograms of symmetrically tilted vortices, taking images in the far-field, and acquiring phase profiles to track the splitting of vortex cores. I find that with this method of vortex generation, higher charge symmetrically tilted vortices remain stable in free-space propagation, offering further insight into the behavior of tilted vortices.