Multiplying vortex beams by diffraction from almost periodic structures: Theory and experiment

We advance theoretically and verify experimentally a protocol for generating arrays of self-similar light beams with the aid of almost periodic structures (APSs), which we refer to as pure amplitude 2N-gonal APSs. We illustrate our general results by realizing a circular array of exact replicas of a Laguerre–Gaussian source beam and registering good agreement between the theory and experiment. Our work carries promise for optical communications, optical tweezing, multi-particle trapping, screening, and micro-manipulation.