The invention and rapid improvement of ultrafast laser technology has enabled several new fields of nonlinear optics and high-intensity laser physics. One area that has received much attention is laser filamentation due to its complex set of underlying nonlinear physics. This dissertation explores the utility of laser filaments by first providing insight into their fundamental characteristics. This is followed by demonstrations of high-energy laser systems that support studies of ultrafast applications in field settings and in new spectral regimes. Initial fundamental studies describe filament wavefront evolution during formation and propagation. These spatially resolved measurements yield new insights into the spatial core-reservoir structure present in fully-formed filaments and the competing optical nonlinearities present during filament collapse and formation. These results inform applications based on multi-filament interaction including nonlinear filament combination and engineered filament arrays. Filament applications are pursued through the activation of the Mobile Ultrafast High-Energy Laser Facility (MU-HELF), a field-deployed system suitable for studying filamentation at the kilometer range in atmospheric conditions. The initial studies supported using the MU-HELF demonstrate the ability to characterize high-energy, multi-filament beams along kilometer paths and correlate these measurements with local metrological effects. This work has also led to the first demonstration of engineered filament arrays at 1 kilometer. A second compact ultrafast laser system based on high-pressure CO2 amplifier technology was deployed alongside the MU-HELF to study ultrafast effects in the long-wave infrared (LWIR). This system enables parallel studies of filamentation in a new spectral regime where filament properties are widely unknown and expected to provide advantages over their near infrared counterparts. Additional LWIR applications are supported including double-resonance spectroscopy, a molecular detection technique capable of providing enhanced molecular discrimination over single-resonant methods at distances and pressures of practical interest.
Doctor of Philosophy (Ph.D.)
College of Optics and Photonics
Optics and Photonics
Optics and Photonics
Length of Campus-only Access
Doctoral Dissertation (Campus-only Access)
Thul, Daniel, "Ultrafast High-energy Laser Systems for Filament Applications" (2020). Electronic Theses and Dissertations, 2020-. 421.