Laser-based inertial fusion energy system enabled by optical enhancement cavities and a direct-drive configuration reactor

Abstract

We propose a novel and highly efficient laser inertial fusion energy reactor concept based on the shock ignition scheme, in which laser-plasma instabilities are mitigated through 500-beam, multicolor, slowly rotating polarization laser beam irradiation. The system employs coherent beam-combined fiber lasers injected into high-finesse optical enhancement cavities, which have already demonstrated energy enhancement factors approaching 60,000 and are expected to surpass 100,000. The 1.06 μ m laser output is frequency-tripled to 0.35 μ m ultraviolet light, resulting in an overall wall-plug-to-ultraviolet-light efficiency of approximately 10%. The reactor integrates a helium-gas-cooled lead-lithium blanket and a direct energy conversion for high-efficiency operation. It is designed for cryogenic deuterium-tritium targets in a direct drive scheme at 1–10 Hz, repetition rate, providing net electric output at 0.1–2.8 GW. This approach offers a compact, scalable, and credible pathway toward practical commercial laser fusion energy.