Optical parametric oscillation with intracavity sum-frequency generation

Theoretical calculations of an optical parametric oscillator containing an intracavity sum-frequency crystal are presented for the case in which only the signal beam from the parametric generation process oscillates in the cavity. The pump beam that is not converted in the parametric generation process is summed with the signal beam to produce a beam at the desired frequency. The stable steady-state configurations that completely deplete the incident pump radiation are determined. When the sum-frequency crystal precedes the parametric-oscillator crystal, steady states with nearly complete pump depletion can occur for over a factor of twelve variation in the pump intensity. Other regimes of operation display period-doubling routes leading to chaotic solutions. A numerical calculation for conversion of 1.064-μm radiation to 589-nm light yields an intensity conversion efficiency of 86.6%