Broad tuning around degeneracy in a singly resonant synchronously pumped parametric oscillator by means of a diffraction grating

The use of a diffraction grating as a frequency-selective reflector, has al lowed a synchronously pumped optical parametric oscillator based on periodi cally poled lithium niobate to tune over a wide range, 1900-2300 nm around degeneracy (2094 nm), on a single periodically poled lithium niobate gratin g at a fixed temperature. The grating ensures stable singly resonant operat ion over the whole of this range except for a very narrow range at degenera cy, where doubly resonant behavior is evident. The extent of this narrow ra nge, similar to 6 nm, is confirmed by analysis. (C) 1999 Optical Society of America [S0740-3224(99)03109-4].