Heat coupled laser rate equations: A model for Er-doped fiber lasers

A heat coupled laser rate equation model was developed to investigate the effects of heat generation on lasing performance. The model was adapted to Er-doped fiber laser. Our model considers thermal depopulation of laser levels when the system is pumped by 1480 nm. The simultaneous solving of coupled heat and laser rate equations gives the laser output and optical gain under the thermal effects along with temperature distribution throughout the fiber. The results could explain the reduction in output signal observed in experimental setups which cannot be explained by the ideal non-thermal model.