Optimum operation of femtosecond parametric oscillation of a noncollinear phase match in KTP

For group-velocity (GV) matching, tunable femtosecond parametric oscillation must use noncollinear phase matching (PM). The tuning curves of femtosecond parametric oscillation are described; tuning can be continuous from the visible to the mid infrared. We demonstrate that GV matching and PM can be satisfied in type II PM for KTP. The effective nonlinear coefficient, the walk-off angles, the acceptance angles (a and thetas), the acceptance spectral width, and the duration of the output idler pulse are calculated. Consequently, optimum femtosecond parametric oscillation of noncollinear phase matching is obtained in KTP.