Filaments and their application to air lasing, spectroscopy, and guided discharge

Author

Ali Rastegari, University of New Mexico - Main CampusFollow

Publication Date

Summer 5-26-2023

Abstract

Laser filamentation is a fascinating phenomenon that occurs when an intense laser beam travels through transparent materials, in particular air. At sufficiently high power (TW in the near IR, GW in the UV), instead of spreading out like a regular laser beam, something remarkable happens: the laser beam becomes tightly focused, creating a thin and intense column of light called a laser filament. Laser filamentation is characterized by two main properties: (I) a high-intensity core that remains narrow over long distances beyond the Rayleigh range and (II) a low-density plasma channel within the core. In recent years, laser filamentation has gained significant attention due to its unique properties and wide range of applications.

This dissertation will provide an introduction to laser filamentation and discuss beam profile measurements related to UV filaments. Additionally, the results of experiments involving the applications of laser filaments will be presented. It has been demonstrated that UV filaments can be utilized for laser breakdown spectroscopy, leading to higher resolution and accuracy. Furthermore, the phenomenon of air lasing induced by both UV and IR laser filaments was investigated. Finally, the potential application of UV filaments for guiding and triggering electrical discharges is studied.

Degree Name

Optical Science and Engineering

Level of Degree

Doctoral

Department Name

Optical Science and Engineering

First Committee Member (Chair)

Dr. Jean-Claude Diels

Second Committee Member

Dr. Alejandro Aceves

Third Committee Member

Dr. Mark Gilmore

Fourth Committee Member

Dr. James Thomas

Keywords

Laser, Filamentation, Air Lasing, Laser Induced Breakdown Spectroscopy (LIBS), Laser Induced Discharge, Ultrashort Pulse Lasers, Nonlinear Optics

Sponsors

Department of Energy (DOE), Airforce Research Lab (AFRL), Army Research Office (ARO)

Document Type

Dissertation

Language

English

Recommended Citation

Rastegari, Ali. "Filaments and their application to air lasing, spectroscopy, and guided discharge." (2023). https://digitalrepository.unm.edu/ose_etds/95