Optical Filtering with Phase Singularities

I worked on constructing an optical filtering device to resolve two separate laser fields very close in frequency which are nearly collinear. It has been demonstrated to be able to achieve four order of magnitude in improvement in the resolution between two laser fields separated by less than a milliradian under ideal conditions. The size of the input fields and pinhole were optimized, and it was found that for our apparatus the field to be filtered should be 3.6 mm in diameter and wanted field to be 2.4 mm with a 0.5 mm pinhole.Such an optical filter will be applied improve the data quality of Prof. Novikova's stored light experiment, which requires two beams, one much more powerful than the other, that exit the experiment nearly collinear such that standard filtering methods are not sufficient. When applied to this experiment, the filter is demonstrated to improve resolution by two orders of magnitude under unideal conditions, and great improvement in performance is expected. The results of experiments to optimize the adjustable parameters of optical vortex coronagraph design, such as the size of the pinhole, control, and probe fields, and the topological charge of the vortex used are presented, and proposed improvements to the coronagraph design discussed