Theoretical Framework and Fabrication Protocols for an Ultra-High Efficiency Optical Rectenna Utilizing MIIM Tunnel Junctions

We report a rigorous theoretical formulation and computational validation for a high- efficiency solar energy harvesting system based on an optical rectenna architecture. By coupling a nanoscale localized surface plasmon resonance (LSPR) gold nano-cone array (32 nm base, 2 nm active apex radius) with an asymmetric Metal-Insulator-Insulator-Metal (MIIM) step-barrier tunneling junction (Pt-HfO2-Al2O3-Ti), the proposed device operates at petahertz frequencies with an effective junction capacitance Cj ≈ 0.28 aF. The com- puted dynamic response demonstrates a cutoff frequency fc > 1.1 PHz, bypassing conven- tional thermalization losses and achieving a theoretical conversion efficiency approaching Landsberg’s thermodynamic limit (93.3%).