Journal of the Optical Society of America B
Optical vortex with a small core and Gaussian intensity envelope for light-matter interaction
Yisa S. Rumala, A. E. Leanhardt
Abstract
Optical vortices with a vortex core size that is at least two orders of magnitude smaller than the laser beam waist is presented. The optical vortex is generated by a spiral phase plate (SPP) and counterrotating optical vortex pairs are created in a modified Mach–Zehnder interferometer surrounded by a 4f lens arrangement. The azimuthal variation of the counterrotating optical vortex forms a sinusoidal intensity modulation for which the winding number of the optical vortex is deduced accurately and precisely by fitting it to a sinusoidal function. These results are of interest in designing novel optical vortex gratings for manipulating matter waves (e.g., in Kapitza–Dirac scattering). A theory of atomic angular Kapitza–Dirac scattering with optical vortices is presented. The large beam waist combined with a small optical vortex core size would also be of interest when using an optical vortex to perform spectroscopy in a wide range of matter systems including solid, liquid, atomic, and molecular systems, as well as in short-range optical communication.