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Title: Raman Amplification with a Flying Focus

Abstract

Here, we propose a new laser amplifier scheme utilizing stimulated Raman scattering in plasma in conjunction with a "flying focus" - a chromatic focusing system combined with a chirped pump beam that provides spatiotemporal control over the pump's focal spot. Pump intensity isosurfaces are made to propagate at v=-c so as to be in sync with the injected counterpropagating seed pulse. By setting the pump intensity in the interaction region to be just about the ionization threshold of the background gas, an ionization wave is produced that travels at a fixed distance ahead of the seed. Simulations show that this will make it possible to optimize the plasma temperature and mitigate many of the issues that are known to have impacted previous Raman amplification experiments, in particular, the growth of precursors.

Authors:
 [1];  [1];  [1];  [1];  [1];  [1];  [1]
  1. Univ. of Rochester, Rochester, NY (United States)
Publication Date:
Research Org.:
Univ. of Rochester, Rochester, NY (United States). Lab. for Laser Energetics
Sponsoring Org.:
USDOE National Nuclear Security Administration (NNSA)
OSTI Identifier:
1417648
Alternate Identifier(s):
OSTI ID: 1416843
Report Number(s):
2017-179, 1366
Journal ID: ISSN 0031-9007; PRLTAO; 2017-179, 2322, 1366; TRN: US1801096
Grant/Contract Number:
NA0001944; SC0016253
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Physical Review Letters
Additional Journal Information:
Journal Volume: 120; Journal Issue: 2; Journal ID: ISSN 0031-9007
Publisher:
American Physical Society (APS)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY

Citation Formats

Turnbull, D., Bucht, S., Davies, A., Haberberger, D., Kessler, T., Shaw, J. L., and Froula, D. H. Raman Amplification with a Flying Focus. United States: N. p., 2018. Web. doi:10.1103/PhysRevLett.120.024801.
Turnbull, D., Bucht, S., Davies, A., Haberberger, D., Kessler, T., Shaw, J. L., & Froula, D. H. Raman Amplification with a Flying Focus. United States. doi:10.1103/PhysRevLett.120.024801.
Turnbull, D., Bucht, S., Davies, A., Haberberger, D., Kessler, T., Shaw, J. L., and Froula, D. H. Fri . "Raman Amplification with a Flying Focus". United States. doi:10.1103/PhysRevLett.120.024801.
@article{osti_1417648,
title = {Raman Amplification with a Flying Focus},
author = {Turnbull, D. and Bucht, S. and Davies, A. and Haberberger, D. and Kessler, T. and Shaw, J. L. and Froula, D. H.},
abstractNote = {Here, we propose a new laser amplifier scheme utilizing stimulated Raman scattering in plasma in conjunction with a "flying focus" - a chromatic focusing system combined with a chirped pump beam that provides spatiotemporal control over the pump's focal spot. Pump intensity isosurfaces are made to propagate at v=-c so as to be in sync with the injected counterpropagating seed pulse. By setting the pump intensity in the interaction region to be just about the ionization threshold of the background gas, an ionization wave is produced that travels at a fixed distance ahead of the seed. Simulations show that this will make it possible to optimize the plasma temperature and mitigate many of the issues that are known to have impacted previous Raman amplification experiments, in particular, the growth of precursors.},
doi = {10.1103/PhysRevLett.120.024801},
journal = {Physical Review Letters},
number = 2,
volume = 120,
place = {United States},
year = {Fri Jan 12 00:00:00 EST 2018},
month = {Fri Jan 12 00:00:00 EST 2018}
}

Journal Article:
Free Publicly Available Full Text
This content will become publicly available on January 12, 2019
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Citation Metrics:
Cited by: 1work
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