Dissertation Title: “Filament Propagation through Atmospheric Conditions”
Abstract: Laser propagation over long ranges is a challenge due to turbulence, aerosols, and other environmental factors. Linear propagation through adverse, real-world environments will often lead to diffraction and distortion of the wave-front. Laser filamentation, which relies on nonlinear propagation, may offer a solution to this challenge. Ultra-short pulse lasers with a sufficient power will experience Kerr self-focusing when propagating through a nonlinear medium such as air. This self-focusing will liberate electrons in the air, forming a plasma. The plasma will defocus the pulse and counteract the self-focusing effects. A balance of these self-focusing and defocusing effects form a plasma channel and an extended region of high intensity propagation. In combination, these are called a laser filament. Filaments are robust, propagating several times the Rayleigh distance and exhibiting properties such as self-healing. Therefore, filaments have the potential to propagate long distances through adverse environments, making them ideal in long-range applications in fields such as communications, machining, defense, and environmental control. To design successful filament applications, filament formation and propagation needs to be well-characterized in non-laboratory conditions. This dissertation explores filamentation in high altitude conditions, in turbulent environments, and interacting with aerosols. Filament formation and propagation, including the pulse preconditions, is modeled and experimentally explored at low pressures. Experimentation over long ranges in turbulent environments validates the use of filaments in real-world conditions. Additionally, spatial and temporal filament structures are introduced to enhance filament propagation and effects in adverse environments.
Educational Career:
BS: 2017, Physics, University of Chicago
MS: 2019, Optics and Photonics, University of Central Florida
Committee in Charge:
Martin Richardson, Chair
Jim Moharam
Romain Gaume
Shermineh Rostami Fairchild, External Member
Michael Chini, External Member
Approved for distribution by Martin Richardson, Committee Chair, on June 20th, 2022.
The public is welcome to attend.
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