Numerical Simulation Design and Implementation of Thulium-Doped Fiber Lasers

The study of fiber lasers in the near-infrared band is of great significance for improving the transmission power and channel capacity of optical communication. Thulium-doped fiber lasers (TDFL) are one of the research focuses in this area. However, the research on TDFL operating in the 1450-1500nm wavelength range is relatively insufficient. In order to expand the application wavelength range of TDFL, this paper analyzes the energy level system of thulium ions, the process of electronic transition, and the structural characteristics of TDFL through numerical simulation. It establishes the rate equation and power propagation equation of a three-level system TDFL using 793nm pump light and operating in the 1450-1500nm wavelength range, proving the feasibility of designing a three-level system TDFL operating in the 1450-1500nm wavelength range. TDFL is capable of achieving satisfactory output power with a fiber length of 1.8m and a doping concentration of 0.6 (×1025/m3). This finding provides a research direction and theoretical reference for the practical application of TDFL.