Abstract

Erbium-doped fiber ring lasers (EFRL) have been receiving increasing attention in telecommunications, optical fiber sensors and spectroscopy.^1,2This paper presents the first, to our knowledge, power performance optimization of tunable EFRL. The optimization is achieved by extending the use of a model based on rate equations for a three-level system where ESA and ASE are not included. The model can be applied to different fiber laser configurations. A Figure of Merit is defined as the ratio of output power $P_s^{\text{out}}$ to the pump power P_paiming to optimize the power conversion efficiency of EFRL. Fig. 1 shows the configuration of the EFRL modeled. Device's performance is investigated for a given signal and pump wavelengths, λ_sand λ_p′respectively, by varying the WDM coupler reflectivity R,the normalized dopedfiber length α_sLand the transmission factor V,that describes the ring cavity losses (doped-fiber not included). The Figure of Merit is normalized to the quantum efficiency, as follows: where η(R,V_t,α_sL) is the normalized slope efficiency, and $P_p^{\text{th}}\left(R,V_t,{\alpha }_{s}L\right)$ is the threshold pump power as derived in Ref. 3, and extended expliciting the dependence of fiber maximum gain on its length.

© 1995 IEEE