Bursting oscillations in optical parametric oscillators

Different forms of bursting oscillations with frequencies from a few MHz to hundreds of MHz separated by intervals of no activity have been observed experimentally for an optical parametric oscillator (OPO) system subject to thermal effects. These oscillations have been simulated numerically using previously derived equations for two interacting transverse modes. In this paper, we investigate one particular case in detail and show that a simple phase-plane analysis explains the bursting cycle. Furthermore, by taking advantage of the values of the parameters, we determine an approximation for the solution of the OPO equations, leading to estimates of the oscillation frequency and of the threshold of the bimode regime