ABSTRACT
This chapter presents a model for high-power lasers based on measurable parameters, which can be used to compare different laser structures and to predict the electro-optical characteristics as a function of cavity length and facet reflectivities. It investigates the profile of the optical power in the cavity in more detail. The chapter discusses several effects responsible for the saturation of the output power with increasing injection current. It derives the parabolic paraxial wave equation based on the slowly varying amplitude and rotating wave approximations, taking into account gain dispersion, spontaneous emission, and a third-order nonlinear susceptibility. The chapter gives a balance equation for the electromagnetic energy density. It also presents the equations that can be used to calculate the nonlinear lateral optical modes of broad-area lasers and discuss several root causes for the multipeaked and not diffraction-limited lateral field profile of broad-area lasers. The chapter summarizes a thermodynamic-based model for the transport of the charged carriers and the temperature flow.
