Optimum output coupling for a mid-infrared KTiOAsO₄ optical parametric oscillator

Abstract

Taking into account the turn off time of the Q-switch, the coupled equations for a mid-infrared KTiOAsO 4 optical parametric oscillator (OPO) are given. These rate equations are solved numerically and some key parameters for designing the laser system are determined. The key parameters include the optimal coupling and nonlinear crystal length which maximize the output power and OPO conversion efficiency. We found that a low-loss singly resonant OPO cavity not only enhances the mid-infrared output but also decreases the optimal OPO crystal length.

The influence of energy transfer upconversion on Q-switched single resonator optical parametric oscillator

“…This is because the pump light intensity in the laser gain medium is attenuated. According to the model presented in [17,19] and taking the spatial distribution into account the rate equations are modified as: , , is population inversion density, c is speed of light in vacuum, σ is the stimulated cross section of laser medium, γ is inversion reduction factor, σ NL is nonlinear gain factor and given by [20]:…”