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arXiv · 2605.14129

A Hybrid Scheme to Achieve Highest Implosion Performance on the OMEGA Laser

P. S. Farmakis·L. Ceurvorst·V. Gopalaswamy·D. Cao·K. S. Anderson·A. Lees·D. Patel·R. Betti
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Abstract

Merging direct and indirect-drive has long been viewed as an optimal hybrid laser-fusion scheme that combines the uniformity of x rays with the efficiency of direct illumination. We present the first integrated 2D simulations of hybrid shock drive (HSD) targets for the OMEGA laser. The HSD scheme [L. Ceurvorst et al., Phys. Rev. E 101 063207 (2020)] uses x rays from a thin Au-coated x-ray converter outer shell to drive the initial shock into a standard direct-drive capsule. Direct illumination is used to implode the target after the first shock. The design effectively suppresses laser-imprint seeding of hydrodynamic instabilities, maintaining shell integrity during the implosion. This scheme will enable fielding low-adiabat, high-convergence implosions on OMEGA with expected performance greatly exceeding those of current designs. HSD targets are projected to significantly enhance fusion yields, potentially increasing the record Lawson parameter by $\sim$85\% on OMEGA while effectively eliminating the requirement for laser smoothing. These results position HSD as a robust platform for high-performance implosions, paving the way for advanced high-gain inertial fusion energy targets.

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P. S. Farmakis, L. Ceurvorst, V. Gopalaswamy, D. Cao, K. S. Anderson, A. Lees, D. Patel, R. Betti. 2026-05-13. A Hybrid Scheme to Achieve Highest Implosion Performance on the OMEGA Laser. https://arxiv.org/abs/2605.14129

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