Technical Summary: StrongArm RTG V3

Abstract: Current space radioisotope thermoelectric generators (RTGs) suffer from limited specific power and poor thermal conversion efficiencies (< 7%). This paper presents a breakthrough architecture, designated "StrongArm", based on an exclusively solid-state hybrid system. By exploiting a porous Strontium-90 (90Sr) Cermet matrix laminated in a "mille-feuille" (multi-layered) structure, we maximize the escape rate of relativistic electrons while leveraging mass self-absorption. The system relies on a dual-stage hybrid conversion cycle: (1) Primary betavoltaic extraction via the excitation of Surface Plasmon-Polaritons in nanostructured 4H-SiC vacuum channels, ensuring autonomous bootstrapping and power for onboard instrumentation. (2) Ultra-high efficiency secondary conversion of the heat—generated by wakefield impedance, inelastic collisions, and Bremsstrahlung absorption—via a Thermophotovoltaic (TPV) interface operating at 1000°C. This integrated static architecture, which includes a compressible storage matrix for transmutation products (90Zr), eliminates moving parts, extends operational lifespan, and targets an overall conversion efficiency exceeding 30%, thereby redefining RTG standards for deep space exploration. (Note: Conceptual framework and manuscript drafted with the assistance of Gemini 3.1)