The paper investigates the generation of THz radiation in the filamentation process. The possibility of increasing the generation efficiency of terahertz (THz) radiation in a single-color filamentation mode excited in air by laser beams with necklace amplitude profile is considered. A stationary model of THz radiation generation is proposed, which allows us to study the dependence of conversion efficiency on the amplitude profiling of pump beams. It is shown that the partitioning of radiation over subapertures allows controlling the energy of THz radiation. The optimal class of gorget beams is found by the genetic algorithm method. The results of this work are important for the development of technologies for remote generation of THz radiation in gaseous media.
single-color THz radiation generation, filamentation, corona-shaped laser beam, genetic algorithm
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