The 9th International Conference on Matter and Radiation at Extremes (ICMRE2026) ( ICMRE2026)

The double-cone ignition (DCI) scheme is a promising inertial confinement fusion approach that decouples compression from ignition using gold cones to guide colliding plasma jets. This scheme significantly lowers the ignition threshold. A key challenge, however, is maintaining the cone's structural integrity under intense dynamic loading during the compression phase. We use a radiation hydrodynamics code to simulate the cone's response to laser ablation and fuel impact during the DCI compression phase. The most severe loading occurs near the cone tip. Fuel impact generates a peak pressure of ~650 Mbar, far exceeding the ~35 Mbar ablation pressure, making it the dominant threat to cone stability. Cone failure is primarily caused by the interaction of rarefaction waves inside the material, formed when shock waves reflect off the free surface. Based on this mechanism, we establish a spallation failure model and provide critical wall thickness conditions to prevent failure before ignition under various laser drive energies. These results can serve as a useful reference for the structural design of DCI cone targets and the evaluation of their integrity during compression.
 

Double-cone ignition; gold cone; spallation; critical thickness