Injection locking of CW ring dye lasers

An analytical treatment of the injection locking of CW dye lasers, taking into account the Fabry-Perot enhancement of the laser cavity is presented. The analysis, restricted to the case where the injected radiation is resonant within the injected resonator, is based on a set of rate equations for the population densities and photon flux. Analytical solutions are found which allow the injection threshold conditions to be easily determined, and which describe the different intracavity intensities characterizing the system. The dependence of these quantities on various parameters such as input coupler transparency, pump intensity, injected intensity, and wavelength is analyzed. These results correct, in the case of steady-state laser operation, the theoretical predictions obtained by Ganiel et al. from a model where only the field intensities were considered instead of the field amplitudes. The experimental feasibility of CW ring dye laser injection locking is discussed and the conditions for an optimum system, in terms of intracavity power are determined.