Mitigation of cross-beam energy transfer in inertial-confinement-fusion plasmas with enhanced laser bandwidth

摘要

Cross-beam energy transfer (CBET) is a significant energy-loss mechanism in directly driven inertialconfinement- fusion (ICF) targets. One strategy for mitigating CBET is to increase the bandwidth of the laser light, thereby disrupting the resonant three-wave interactions that underlie this nonlinear scattering process. Here, we report on numerical simulations performed with the wave-based code LPSE that show a significant reduction in CBET for bandwidths of 2 – 5 THz (corresponding to a normalized bandwidth of 0.2% – 0.6% at a laser wavelength of 351 nm) under realistic plasma conditions. Such bandwidths are beyond those available with current high-energy lasers used for ICF, but could be achieved using stimulated rotation Raman scattering in diatomic gases like nitrogen.