J.D. Marconi

Spectrally flat and broadband double-pumped fiber optical parametric amplifiers

We study theoretically and experimentally spectrally flat and broadband double-pumped fiber-optical parametric amplifiers (2P-FOPAs). Closed formulas are derived for the gain ripple in 2P-FOPAs as a function of the pump wavelength separation and power, and the fiber non-linearity and fourth order dispersion coefficients. The impact of longitudinal random variations of the zero dispersion wavelength (lambda(0)) on the gain flatness is investigated. Our theoretical findings are substantiated with experiments using conventional dispersion shifted fibers and highly nonlinear fibers (HNLFs). By using a HNLF having a low variation of lambda0 we demonstrate high gain and flat spectrum (25 +/- 1.5 dB) over 115 nm.

Double-pumped fiber optical parametric amplifier with flat gain over 47-nm bandwidth using a conventional dispersion-shifted fiber

We investigate the performance of conventional dispersion-shifted fibers (DSFs) as nonlinear medium in double-pumped fiber optical parametric amplifiers (2P-FOPAs). We report on high gain (37 dB) with low ripple (/spl plusmn/1.5 dB) over a 47-nm bandwidth using these fibers. We show that the 2P-FOPA average gain and the gain uniformity are limited by longitudinal variations of the zero dispersion wavelength and by polarization-mode dispersion. We demonstrate that 2P-FOPAs constructed with DSFs exhibit negligible crosstalk even for high gains (40 dB) and large output signal powers (12.5 dBm) in a ten-channel system.

High performance hybrid EDFA-FOPA pre-amplifier for 40 Gb/s transmission

We demonstrated a novel application of a FOPA, i.e. the operation of a hybrid pre-amplifier built with a single-pump FOPA as a second stage of an EDFA pre-amplifier and its application on a 40-Gb/s system.

Nearly 100 nm bandwidth of flat gain with a double-pumped fiber optic parametric amplifier

We demonstrate double-pumped fiber-optical parametric amplifiers with flat and broadband gain spectrum. Using specially fabricated highly non-linear fibers having low variations of the zero-dispersion wavelength and low PMD we obtain flat gain (23.5plusmn1dB) over ~95 nm.

A novel method for measuring longitudinal variations of the zero dispersion wavelength in optical fibers

We report on a fast method based on four-wave-mixing between a tunable-laser and an ASE source for measuring longitudinal variations of the zero-dispersion wavelength in optical fibers. We measure this variation with 0.05nm resolution.

Q penalties due to pump phase modulation in FOPAs

We investigate Q penalties in FOPAs arising from variations of the parametric gain originated by pump phase modulation. We show that these penalties are strongly reduced in fibers with large variations of the zero dispersion wavelength (lambda0)

Multiple four-wave mixing in ultra-flattened dispersion photonic crystal fibers

The generation of multiple four-wave mixing products in ultra-flattened dispersion photonic crystal fibers is presented. We obtained more than 200 products spanning over 170 nm by launching 3 lasers at ITU-T grid specification.

All-optical generation of quaternary amplitude-shift keying signals through parametric amplification

In this work we present experimental results concerning a new technique that uses parametric amplification to merge two binary signals into a single quaternary amplitude-shift keying (4-ASK) signal. We also propagate such quaternary signal through a 75-km long standard fibre link; the measured eye-opening penalty was lower than 1 dB.

Laser generation with a microstructured Er 3+ -doped tellurite optical fiber

We fabricate a microstructured Erbium-doped tellurite fiber and demonstrate laser emission. A simple double-pump configuration (980 nm) is used. A 5 cm fiber generates a laser at 1553.3 nm with an OSNR of ~21 dB.

Full nonlinear conversion of a 200 nm comb produced by multiple four-wave mixing in a highly nonlinear fiber

A 100-nm comb of optical frequencies spaced by 400 GHz at 790 nm was obtained by second harmonic generation of an optical frequency comb produced by multiple four-wave-mixing in a highly nonlinear optical fiber.