High-repetition-rate femtosecond optical parametric oscillator based on periodically poled lithium niobate

A high-repetition-rate, femtosecond optical parametric oscillator based on bulk periodically poled lithium niobate is described. This optical parametric oscillator is continuously tunable from 1.12 to 1.50 μm in the signal branch, and signal pulses as short as 60 fs have been observed. The corresponding turning range for the idler branch is from 1.68 to 2.72 μm. Modifications which should result in a femtosecond optical parametric oscillator with a pumping threshold of less than 50 mW are discussed.