Relationship of Nonlinear Gain to Nonlinear Refraction in Quantum-Well Lasers

The effect of nonlinear gain mechanisms, such as dynamic heating of carriers by radiation, and burnup of spatial and spectral gaps, on the real and imaginary parts of the refractive index is examined. The dependence of the effective amplitude–phase coupling parameter for nonlinear gain on emission frequency and pump level is established. Dynamic heating is shown to be the main mechanism for the nonlinear gain determining the above parameter.