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Terawatt Laser Pulse Propagation in Gaseous Media
Terawatt Laser Pulse Propagation in Gaseous Media
상세정보
- 자료유형
- 학위논문 서양
- 최종처리일시
- 20260202103134
- ISBN
- 9798280751705
- DDC
- 530
- 서명/저자
- Terawatt Laser Pulse Propagation in Gaseous Media
- 발행사항
- [Sl] : Princeton University, 2025
- 발행사항
- Ann Arbor : ProQuest Dissertations & Theses, 2025
- 형태사항
- 144 p
- 주기사항
- Source: Dissertations Abstracts International, Volume: 86-12, Section: B.
- 주기사항
- Advisor: Mikhailova, Julia.
- 학위논문주기
- Thesis (Ph.D.)--Princeton University, 2025.
- 초록/해제
- 요약Propagation of high-power femtosecond laser beams in gaseous media has been studied extensively in the last several decades because of its potential for delivering high power over large distances in atmosphere, producing terahertz radiation, generating coherent supercontinuum and ultrashort light pulses, as well as for applications in laser diagnostics of flows and combustion environments. These applications are often hindered by the breakup of the laser beam into multiple filaments in the transverse cross-section that occurs when the laser power exceeds the critical power of self-focusing. The formation of multiple filaments leads to a loss of coherence in the beam and dissipation of its energy which is a major obstacle for applications.This thesis explores propagation of terawatt-power femtosecond laser beams in atmospheric gases under varying interaction conditions. Spectral and spatial transformations of terawatt beams as well as ultrafast ionization of gases are investigated as a function of gas composition, pressure, pulse energy, and laser focusing conditions. Three experimental setups - one based on transmissive focusing optics, and two all-reflective setups - are used for these studies. It is shown that low gas pressures allow for substantial nonlinear spectral broadening of terawatt laser beams without significant degradation of their spatial quality necessary for applications. Additionally, spatial distributions of the spectra, crucial for efficient compression of the laser pulses, and strong line emission from nitrogen ions is studied and discussed.The theoretical scaling laws of the high-power femtosecond laser propagation dynamics are discussed for different focusing conditions, gas composition, pressure, and laser pulse energy. In addition, the ultrafast ionization of gases during propagation of high-power beams was characterized with interferometry. Plasma emission spectra and profiles have also been measured and discussed. The interferometric measurements of the plasma density were correlated with the laser's spectral broadening to determine the contribution of plasma formation to the measured spectral width. This approach is used to evaluate the relative impacts of plasma formation and nonlinear Kerr self-focusing on the dynamics of the system. Finally, future applications of the above-mentioned phenomena for powerful broadband THz radiation generation are discussed and a method for its efficiency enhancement is proposed.
- 일반주제명
- Plasma physics
- 일반주제명
- Optics
- 일반주제명
- Aerospace engineering
- 키워드
- Femtosecond
- 키워드
- Filamentation
- 키워드
- Laser
- 키워드
- Plasma
- 키워드
- Propagation
- 기타저자
- Princeton University Mechanical and Aerospace Engineering
- 기본자료저록
- Dissertations Abstracts International. 86-12B.
- 전자적 위치 및 접속
- 로그인 후 원문을 볼 수 있습니다.
MARC
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■00520260202103134
■006m o d
■007cr#unu||||||||
■020 ▼a9798280751705
■035 ▼a(MiAaPQ)AAI31940708
■040 ▼aMiAaPQ▼cMiAaPQ
■0820 ▼a530
■1001 ▼aGiakas, Andreas Michael.▼0(orcid)0009-0002-2216-3604
■24510▼aTerawatt Laser Pulse Propagation in Gaseous Media
■260 ▼a[Sl]▼bPrinceton University▼c2025
■260 1▼aAnn Arbor▼bProQuest Dissertations & Theses▼c2025
■300 ▼a144 p
■500 ▼aSource: Dissertations Abstracts International, Volume: 86-12, Section: B.
■500 ▼aAdvisor: Mikhailova, Julia.
■5021 ▼aThesis (Ph.D.)--Princeton University, 2025.
■520 ▼aPropagation of high-power femtosecond laser beams in gaseous media has been studied extensively in the last several decades because of its potential for delivering high power over large distances in atmosphere, producing terahertz radiation, generating coherent supercontinuum and ultrashort light pulses, as well as for applications in laser diagnostics of flows and combustion environments. These applications are often hindered by the breakup of the laser beam into multiple filaments in the transverse cross-section that occurs when the laser power exceeds the critical power of self-focusing. The formation of multiple filaments leads to a loss of coherence in the beam and dissipation of its energy which is a major obstacle for applications.This thesis explores propagation of terawatt-power femtosecond laser beams in atmospheric gases under varying interaction conditions. Spectral and spatial transformations of terawatt beams as well as ultrafast ionization of gases are investigated as a function of gas composition, pressure, pulse energy, and laser focusing conditions. Three experimental setups - one based on transmissive focusing optics, and two all-reflective setups - are used for these studies. It is shown that low gas pressures allow for substantial nonlinear spectral broadening of terawatt laser beams without significant degradation of their spatial quality necessary for applications. Additionally, spatial distributions of the spectra, crucial for efficient compression of the laser pulses, and strong line emission from nitrogen ions is studied and discussed.The theoretical scaling laws of the high-power femtosecond laser propagation dynamics are discussed for different focusing conditions, gas composition, pressure, and laser pulse energy. In addition, the ultrafast ionization of gases during propagation of high-power beams was characterized with interferometry. Plasma emission spectra and profiles have also been measured and discussed. The interferometric measurements of the plasma density were correlated with the laser's spectral broadening to determine the contribution of plasma formation to the measured spectral width. This approach is used to evaluate the relative impacts of plasma formation and nonlinear Kerr self-focusing on the dynamics of the system. Finally, future applications of the above-mentioned phenomena for powerful broadband THz radiation generation are discussed and a method for its efficiency enhancement is proposed.
■590 ▼aSchool code: 0181.
■650 4▼aPlasma physics
■650 4▼aOptics
■650 4▼aAerospace engineering
■653 ▼aFemtosecond
■653 ▼aFilamentation
■653 ▼aLaser
■653 ▼aNonlinear spectral broadening
■653 ▼aPlasma
■653 ▼aPropagation
■690 ▼a0759
■690 ▼a0752
■690 ▼a0538
■71020▼aPrinceton University▼bMechanical and Aerospace Engineering.
■7730 ▼tDissertations Abstracts International▼g86-12B.
■790 ▼a0181
■791 ▼aPh.D.
■792 ▼a2025
■793 ▼aEnglish
■85640▼uhttp://www.riss.kr/pdu/ddodLink.do?id=T17357120▼nKERIS▼z이 자료의 원문은 한국교육학술정보원에서 제공합니다.
