General model for a multimode Nd-doped fiber laser. I: Construction of the model

Abstract.

We present a general modeling of a multi-longi-tudinal-mode bipolarized Nd-doped fiber laser which keeps both vectorial (polarization) and longitudinal properties in the dynamical equations. We use an approach based on random orientation of the microscopic dipoles and demonstrate that it is isomorphic to the model derived assuming a transverse two-site distribution function for the ions. This result is also true under the mean-field approximation. At steady-state, the model is the generalization of Rigrod’s theory to the case of a bipolarized laser.