Quantum mechanics

Erbium

Engineering

Materials science

Clamping

Atomic physics

Mechanical engineering

Laser

Energy transfer

Physics

Rate equation

Optics

Doping

Kinetics

Lasing threshold

Fiber laser

Optoelectronics

Ytterbium

Optics Express

Conventional models of Er/Yb co-doped fibers assume all ytterbium ions are equally involved in the energy transfer with erbium ions, governed by a singular transfer rate. This would predict output power clamping once ytterbium parasitic lasing starts, contrary to the observations that the output continued to grow albeit at a slower rate. One study explained this using elevated temperature at high powers. Our study, however, shows that elevated temperature and mode-dependent effects only play insignificant roles. A new model is developed based on the existence of isolated ytterbium ions, which can explain all the observed experimental behaviors.

Modeling Er/Yb fiber lasers at high powers