FEMTOSECOND OPTICAL PARAMETRIC OSCILLATOR BASED ON PERIODICALLY POLEDKTIOPO4

We report a femtosecond optical parametric oscillator based on a perio dically poled KTiOPO4 crystal for which quasi-phase matching is achiev ed with a 24-mu m poling period. The singly resonant parametric oscill ator, synchronously pumped by a Ti:sapphire laser at a wavelength of 7 58 nm, generates a signal at 1200 nm and an idler at 2060 nm. The maxi mum signal power conversion efficiency of the device is 22% with a pum p depletion of 69%. We tune the signal wavelength over a 200-nm band b y changing the cavity length. In addition, pump wavelength tuning prov ides output tunability in the 1000-1235-nm range. (C) 1998 Optical Soc iety of America.