Beyond the random phase approximation: Stimulated Brillouin backscatter for finite laser coherence times
Abstract
We developed a linear theory of backward stimulated Brillouin scatter (BSBS) of a spatially and temporally random laser beam relevant for laser fusion. Our analysis reveals a new collective regime of BSBS (CBSBS). Its intensity threshold is controlled by diffraction, once cT{sub c} exceeds a laser speckle length, with T{sub c} the laser coherence time. The BSBS spatial gain rate is approximately the sum of that due to CBSBS, and a part which is independent of diffraction and varies linearly with T{sub c}. The CBSBS spatial gain rate may be reduced significantly by the temporal bandwidth of KrFbased laser systems compared to the bandwidth currently available to temporally smoothed glassbased laser systems.
 Authors:
 Department of Mathematics and Statistics, University of New Mexico, Albuquerque, New Mexico 87131 (United States)
 (Russian Federation)
 Theoretical Division, Los Alamos National Laboratory, MSB213, Los Alamos, New Mexico 87545 (United States)
 (United States)
 Publication Date:
 OSTI Identifier:
 22407985
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physics of Plasmas; Journal Volume: 22; Journal Issue: 1; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; BACKSCATTERING; DIFFRACTION; LASERS; PHOTON BEAMS; RANDOM PHASE APPROXIMATION; RANDOMNESS
Citation Formats
Korotkevich, Alexander O., Lushnikov, Pavel M., Email: plushnik@math.unm.edu, Landau Institute for Theoretical Physics, 2 Kosygin Str., Moscow 119334, Rose, Harvey A., and New Mexico Consortium, Los Alamos, New Mexico 87544. Beyond the random phase approximation: Stimulated Brillouin backscatter for finite laser coherence times. United States: N. p., 2015.
Web. doi:10.1063/1.4906057.
Korotkevich, Alexander O., Lushnikov, Pavel M., Email: plushnik@math.unm.edu, Landau Institute for Theoretical Physics, 2 Kosygin Str., Moscow 119334, Rose, Harvey A., & New Mexico Consortium, Los Alamos, New Mexico 87544. Beyond the random phase approximation: Stimulated Brillouin backscatter for finite laser coherence times. United States. doi:10.1063/1.4906057.
Korotkevich, Alexander O., Lushnikov, Pavel M., Email: plushnik@math.unm.edu, Landau Institute for Theoretical Physics, 2 Kosygin Str., Moscow 119334, Rose, Harvey A., and New Mexico Consortium, Los Alamos, New Mexico 87544. 2015.
"Beyond the random phase approximation: Stimulated Brillouin backscatter for finite laser coherence times". United States.
doi:10.1063/1.4906057.
@article{osti_22407985,
title = {Beyond the random phase approximation: Stimulated Brillouin backscatter for finite laser coherence times},
author = {Korotkevich, Alexander O. and Lushnikov, Pavel M., Email: plushnik@math.unm.edu and Landau Institute for Theoretical Physics, 2 Kosygin Str., Moscow 119334 and Rose, Harvey A. and New Mexico Consortium, Los Alamos, New Mexico 87544},
abstractNote = {We developed a linear theory of backward stimulated Brillouin scatter (BSBS) of a spatially and temporally random laser beam relevant for laser fusion. Our analysis reveals a new collective regime of BSBS (CBSBS). Its intensity threshold is controlled by diffraction, once cT{sub c} exceeds a laser speckle length, with T{sub c} the laser coherence time. The BSBS spatial gain rate is approximately the sum of that due to CBSBS, and a part which is independent of diffraction and varies linearly with T{sub c}. The CBSBS spatial gain rate may be reduced significantly by the temporal bandwidth of KrFbased laser systems compared to the bandwidth currently available to temporally smoothed glassbased laser systems.},
doi = {10.1063/1.4906057},
journal = {Physics of Plasmas},
number = 1,
volume = 22,
place = {United States},
year = 2015,
month = 1
}
DOI: 10.1063/1.4906057
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