Threshold of a Single Resonant Optical Parametric Oscillator for a Flat Top Gaussian Beam
T. Wang, X-H. Kong, Q. Liu, P-F. Du, D-X. Geng and M-L. Gong
The threshold of a single resonant optical parametric oscillator for a flat top Gaussian beam is calculated. Comparing to the results for plane waves and the single-mode Gaussian beam, the threshold expression is more general. When the order N → ∞, the expression equals to the threshold for plane wave, and when N = 0, the expression equals to the threshold for flat top Gaussian beam. Before calculation, three-wave coupled equations for flat top Gaussian beam in nonlinear media are derived. The form of the three-wave coupled equations for flat top Gaussian beam is similar to the equations derived based on the plane wave, except that the amplitude is a complex number instead of a real number derived by the plane wave.
Keywords: Optical parametric oscillator, flat top Gaussian beam, threshold, three-wave coupled equations, plane wave, non-linear media, x-cut KTA