Approximate Lasing Condition

Abstract

The system of coupled kinetic rate equations and radiative transfer equations governing an optically active medium is considered, and an approximate lasing condition is established. The lasing condition and the rate equations then form a complete set of equations from which the population densities and radiation energy density can be determined without recourse to the more complicated radiation transfer equations. In this approximation the final expression for the laser power output is found to be identical with the exact solution.