Nonlinear theory for laser diodes

This paper outlines a nonlinear theory for the output power vs excitation current of an injection diode laser. The dependence upon electric field amplitude of effective negative conductivity in the region of inverted population derived and used to determine the level of steady oscillation in the quasilinear approximation (nonlinear conduction current small compared with displacement current). This level is simply related to the output power. A field dependent negative conduction current is derived from the negative conductivity which indicates that, in the quasilinear approximation, the presence of two modes with the same polarization will be an unstable situation; one mode will grow at the expense of the other.