PULSED DEGENERATE OPTICAL PARAMETRIC OSCILLATOR BASED ON A NONLINEAR-FIBER SAGNAC INTERFEROMETER

We report operation of an all-fiber degenerate optical parametric osci llator that employs a nonlinear-fiber Sagnac interferometer as a param etric amplifier. Synchronous pumping with 3.9-ps pulses at 1544 nm yie lds 0.83-ps output pulses. The wide bandwidth of the fiber parametric amplifier causes the oscillator to act as a pulse compressor. The outp ut signal pulses exhibit improved spectral symmetry and a reduced time -bandwidth product compared with the pump pulses. Currently, the net g roup-velocity dispersion in the passive section of the fiber cavity li mits the signal-pulse bandwidth and hence the minimum-obtainable pulse width. This experiment suggests the possibility of frequency conversi on by operation of a similar pulsed parametric oscillator away from de generacy. (C) 1998 Optical Society of America.