Material constraint-based laser performance estimation of Yb3+-doped phosphate fibers

Based on the material properties of 47 Yb3+-doped phosphate fibers with different sizes and lengths, a laser performance estimation model was established to estimate the laser wavelength just above the threshold (lambda(th)), the laser threshold (P-th), and the laser slope efficiency (eta). This model was solved via a numerical computing method with an accuracy of 0.01. Under the material constraints of this model, lambda(th), P-th, and eta were investigated by sensitivity analysis and Monte Carlo numerical simulation. The results show that short fibers with a small core diameter may more easily produce a shorter lambda(th). Additionally, for constant material properties, fibers with a longer lambda(th) may have a lower P-th and higher eta than other fibers. Verifying the above conjecture, an output power of 8.7 W with 35% enhancement in slope efficiency was obtained from an optimized phosphate fiber for an optical path in which the output of the short-wave laser was inhibited. This model can be extended to simulate the lasing wavelength of multi-composition fibers, providing a theoretical basis for special laser bands, laser material preparation, and fiber structure design.