Modelling ASE in High Energy Gas Optics

Xcimer's inertial fusion energy (IFE) hybrid drive concept [1] proposes the use of stimulated rotational Raman (SRRS) and stimulated Brillouin scattering (SBS) in simple gases for high energy beam combination and amplification. Understanding and controlling amplified spontaneous emission in SRRS and SBS is important in delivering energy to the IFE target at high efficiencies. We have developed a modular Monte Carlo (MC) algorithm that can model ASE due to various sources for high energy laser pulses. The modularity allows for the use of arbitrary scattering dynamic structure factors such as kinetic spontaneous Brillouin scattering, spontaneous Raman scattering, and Rayleigh scattering [2]. Results will be shown on expected ASE for high energy pulses due to spontaneous Brillouin and Raman scattering.

[1] C. A. Thomas, M. Tabak, N. B. Alexander, C. D. Galloway, E. M. Campbell, M. P. Farrell, J. L. Kline, D. S. Montgomery, M. J. Schmitt, A. R. Christopherson, and A. Valys. 2024. Hybrid direct drive with a two-sided ultraviolet laser. Physics of Plasmas 31, 11 (November 2024). DOI:https://doi.org/10.1063/5.0221201

[2] Greytak, T. J., & Benedek, G. B. (1966). Spectrum of light scattered from thermal fluctuations in gases. Physical Review Letters, 17(4), 179.