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Controlling formation of femtosecond laser filaments on vertical path in turbulent atmosphere.
Chair of General Physics and Wave Processing. Physics Faculty of MSU.

Markov Andrey.

Diploma thesis abstract.
The ability to control filamentation in powerful femtosecond laser pulses, propagating on kilometer range vertical atmospheric path in the condition of random fluctuations of refraction index., was numerically investigated. Laser pulses with initial peak power exceeding critical power of self-focusing in 10 and more times were used. It was proved that for such laser pulses increase of value of structure constant of atmospheric turbulence leads to earlier formation of the first "hot spot" and to increase of statistical straggling of this distance regardless of used method to control formation of filament. The ability of using focused and chirped was investigated as well as using telescope to increase transversal size of the beam. Joint application of these methods for controlling formation of filaments was also studied. It was demonstrated that it is desirable to use focused laser beams in order to decrease statistical straggling of the distance to formation of filaments. When using lenses with the same focal length it is preferably to increase the size of the beam using telescope in comparison with using phase modulation in order to avoid too early formation of filaments.

Research supervisor, PhD, associate professor

Shlenov S..