Polarization unstabilities in a quasi-isotropic He-Ne laser in axial magnetic field

Abstract

On the basis of the general Lamb model the set of six coupled nonlinear differential equations has been derived for two-mode l = 0.63 mm laser operation with the presence both amplitude and phase anisotropy and axial magnetic field. Numeric integration of the set of equations and the Lyapunov stability analysis have been proceeded. It turned out that in zero magnetic field in the presence of the amplitude anisotropy both stable time-independed states with parallelly or orthogonally polarized modes and non-stationary state are possible. Changing orientation and nonorthogonality/nonparallelity of polarization planes in magnetic field are considered. Influence of mode-mode interaction is discussed.