Group velocity and pulse lengthening of mismatched laser pulses in plasma channels
Abstract
Analytic solutions are presented to the non-paraxial wave equation describing an ultra-short, low-power, laser pulse propagating in aplasma channel. Expressions for the laser pulse centroid motion and laser group velocity are derived, valid for matched and mismatchedpropagation in a parabolic plasma channel, as well as in vacuum, for an arbitrary Laguerre-Gaussian laser mode. The group velocity of amismatched laser pulse, for which the laser spot size is strongly oscillating, is found to be independent of propagation distance andsignificantly less than that of a matched pulse. Laser pulse lengthening of a mismatched pulse owing to laser mode slippage isexamined and found to dominate over that due to dispersive pulse spreading for sufficiently long pulses. Analytic results are shown tobe in excellent agreement with numerical solutions of the full Maxwell equations coupled to the plasma response. Implications for plasmachannel diagnostics are discussed.
- Authors:
- Publication Date:
- Research Org.:
- Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
- Sponsoring Org.:
- Accelerator& Fusion Research Division
- OSTI Identifier:
- 1048294
- Report Number(s):
- LBNL-4976E
Journal ID: ISSN 1070-664X; PHPAEN; TRN: US1204160
- DOE Contract Number:
- DE-AC02-05CH11231
- Resource Type:
- Journal Article
- Journal Name:
- Physics of Plasmas
- Additional Journal Information:
- Journal Name: Physics of Plasmas; Journal ID: ISSN 1070-664X
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; LASERS; MAXWELL EQUATIONS; NUMERICAL SOLUTION; PLASMA; VELOCITY; WAVE EQUATIONS
Citation Formats
Schroeder, Carl, Benedetti, Carlo, Esarey, Eric, van Tilborg, Jeroen, and Leemans, Wim. Group velocity and pulse lengthening of mismatched laser pulses in plasma channels. United States: N. p., 2011.
Web. doi:10.1063/1.3609778.
Schroeder, Carl, Benedetti, Carlo, Esarey, Eric, van Tilborg, Jeroen, & Leemans, Wim. Group velocity and pulse lengthening of mismatched laser pulses in plasma channels. United States. https://doi.org/10.1063/1.3609778
Schroeder, Carl, Benedetti, Carlo, Esarey, Eric, van Tilborg, Jeroen, and Leemans, Wim. 2011.
"Group velocity and pulse lengthening of mismatched laser pulses in plasma channels". United States. https://doi.org/10.1063/1.3609778. https://www.osti.gov/servlets/purl/1048294.
@article{osti_1048294,
title = {Group velocity and pulse lengthening of mismatched laser pulses in plasma channels},
author = {Schroeder, Carl and Benedetti, Carlo and Esarey, Eric and van Tilborg, Jeroen and Leemans, Wim},
abstractNote = {Analytic solutions are presented to the non-paraxial wave equation describing an ultra-short, low-power, laser pulse propagating in aplasma channel. Expressions for the laser pulse centroid motion and laser group velocity are derived, valid for matched and mismatchedpropagation in a parabolic plasma channel, as well as in vacuum, for an arbitrary Laguerre-Gaussian laser mode. The group velocity of amismatched laser pulse, for which the laser spot size is strongly oscillating, is found to be independent of propagation distance andsignificantly less than that of a matched pulse. Laser pulse lengthening of a mismatched pulse owing to laser mode slippage isexamined and found to dominate over that due to dispersive pulse spreading for sufficiently long pulses. Analytic results are shown tobe in excellent agreement with numerical solutions of the full Maxwell equations coupled to the plasma response. Implications for plasmachannel diagnostics are discussed.},
doi = {10.1063/1.3609778},
url = {https://www.osti.gov/biblio/1048294},
journal = {Physics of Plasmas},
issn = {1070-664X},
number = ,
volume = ,
place = {United States},
year = {Thu Jul 07 00:00:00 EDT 2011},
month = {Thu Jul 07 00:00:00 EDT 2011}
}