Optimizing Few-Mode Erbium-Doped Fiber Amplifiers for high-capacity optical networks using a multi-objective optimization algorithm

Abstract

In this paper, an optimized design for a Few-Mode Erbium-Doped Fiber Amplifier (FM-EDFA) is presented, using a Genetic Algorithm (GA) for multi-objective optimization of gain, noise figure (NF), and differential modal gain (DMG) across multiple modes. The GA explored a three-layer erbium doping profile structure to support four mode groups (${\text{LP}}_{01}$, ${\text{LP}}_{11a/b}$, ${\text{LP}}_{21a/b}$, and ${\text{LP}}_{02}$). Results demonstrated that an optimized two-layer configuration was sufficient to achieve low DMG, low NF, and consistent high gain across modes, essential for long-haul space-division multiplexing (SDM) systems. MATLAB simulations validated the FM-EDFA performance under varying doping profiles, revealing a robust balance of gain, DMG, and NF for multimode amplification. This optimized FM-EDFA model supports high-capacity SDM transmission with stable, uniform amplification, offering valuable insights into efficient amplifier design for next-generation optical networks.