Spectral properties of the single beams generated by an optical parametric oscillator

The quantum nature of the parametric interaction affects the spectral properties of the single output beams in a way which depends critically on the damping coefficients of the signal, idler and pump modes. When they are of the same order relaxation oscillations appear in the single-beam spectra. The single outputs are described in the frequency domain by analytic transfer functions, representing the system response to white noise sources. We report numerical simulations of the single-beam spectra referring to different optical parametric oscillator working conditions. In particular we study how these spectra depend on detuning, pumping level and cavity dampings to better clarify the conditions for which relaxation oscillations appear