Glenn D. Bartolini

All-optical storage of a picosecond-pulse packet using parametric amplification

We demonstrate all-optical storage of a picosecond-pulse packet of ones and zeros in a fiber buffer in which loss is compensated by parametric amplification. An all-fiber phase-sensitive parametric amplifier, which exploits a nonlinear Sagnac loop made of standard polarization-maintaining fiber to provide gain, regenerates the stored pulses on each round-trip. Storage for periods of time tip to 1 ms has been observed. Data packets of 10s of kilobits could be stored in this device with use of a higher repetition-rate pump source.

Pulsed degenerate optical parametric oscillator based on a nonlinear-fiber Sagnac interferometer

We report operation of an all-fiber degenerate optical parametric oscillator that employs a nonlinear-fiber Sagnac interferometer as a parametric amplifier. Synchronous pumping with 3.9-ps pulses at 1544 nm yields 0.83-ps output pulses. The wide bandwidth of the fiber parametric amplifier causes the oscillator to act as a pulse compressor. The output signal pulses exhibit improved spectral symmetry and a reduced time-bandwidth product compared with the pump pulses. Currently, the net group-velocity dispersion in the passive section of the fiber cavity limits the signal-pulse bandwidth and hence the minimum-obtainable pulse width. This experiment suggests the possibility of frequency conversion by operation of a similar pulsed parametric oscillator away from degeneracy.

Rate multiplication of a 59-GHz soliton source at 1550 nm

We demonstrate an all-optical scheme to multiply the repetition frequency of a high-rate optical pulse train by using a spectral filter to remove unwanted frequency components. A stable 58.5-GHz soliton pulse source at 1542 nm is filtered with a Fahry-Perot interferometer to achieve 117 and 175.5 GWz output pulse trains. This scheme is generally applicable to rate multiplication of mode-locked pulse trains using various types of spectral filters. All-optical rate conversion of continuous pulse trains may find applications in time division multiplexed optical networks at high bit rates, where electronic methods are cumbersome.

Rate doubling of a highly stable soliton source

We have proposed spectral filtering as a means of rate multiplication, emphasizing the analogy with a quartz crystal oscillator. As a demonstration, we have used a Fabry-Perot (FP) cavity to produce modulation at twice the fundamental soliton repetition rate. Modulation at any harmonic of the fundamental rate could be obtained by adjusting the FP cavity length, provided that the cavity linewidth remains narrower than the soliton repetition frequency. In particular, tuning to an odd harmonic would transmit two equal-amplitude satellite modes, which could be compressed to produce a soliton pulse stream at an odd multiple of the fundamental repetition rate.

All-optical storage of a picosecond-pulse packet using parametric amplification: demonstration of single-shot loading

We demonstrate all-optical storage of a picosecond-pulse packet of ones and zeros in a fiber buffer in which loss is compensated by parametric amplification. An all-fiber phase-sensitive parametric amplifier, which exploits a nonlinear Sagnac loop made of standard polarization-maintaining fiber to provide gain, regenerates the stored pulses on each round-trip. Storage for periods of time tip to 1 ms has been observed. Data packets of 10s of kilobits could be stored in this device with use of a higher repetition-rate pump source.