Optimization of Power in Pseudo-Nondiffracting Structured Laser Beams for Long-Distance Propagation

Structured laser beams (SLBs) are pseudo-nondiffracting beams with a narrow inner core (IC), whose size can be tuned by adjusting the parameters of the SLB generator. This work characterizes the power distribution of SLBs with different core sizes and explores strategies to increase the power concentrated in the IC. Experiments with beams propagating for 420 and 1000 m demonstrated that optimized illumination patterns can enhance IC power. For small-core SLBs, the IC power was increased by a factor of three through ring beam illumination, while for large-core SLBs, the power was more than doubled by decreasing the diameter of the illuminating Gaussian beam. The study further revealed that the IC power depends on the generator parameters and found optimal parameters that yield the maximum power. These results underline the potential of SLBs to provide intense narrow beams over propagation distances of hundreds of meters.