Analysis of the Influence of Multi-point Pumping on the Gain in an Optical Fiber Amplifier

Gain is an essential technical parameter of fiber amplifiers. The pumping mode and coupling efficiency significantly impact the gain of optical fiber amplifiers. The pumping mode of a traditional optical fiber amplifier is constrained by the amplifier’s gain and the challenge of increasing the output power due to the finite number of pumps. This paper proposes the multipoint side pump coupling mode, which substantially enhances the pump optical power within the fiber through multipoint superposition, thereby improving the fiber amplifier’s gain. A model for multipoint pump optical power is established to analyze the feasibility of enhancing power through multipoint pumping. Using Optisystem software, we construct an Erbium-Yterbium (Er-Yb) codoped fiber cladding amplifier (EYDFA) system with multipoint side pump coupling and simulate and analyze the influence of the fiber length between pumps on the overall amplifier gain.