Stephane Petit

Controlling Optical Signals Through Parametric Processes

Parametric processes are capable of preserving the phase information of optical signals while their frequencies are converted. This feature, in conjunction with other basic features such as instantaneous and wideband operation, low noise, and high reliability, creates various unique functionalities in optical domain, invaluable for realizing future dynamic all optical networks that are scalable in capacity without energy crunch. This paper will review the fundamentals and proof of concept of the parametric devices that authors have been proposing as important building blocks for the future networks. The devices to be reviewed are parametric wavelength converters, parametric tunable dispersion compensators, parametric delay dispersion tuners, and wavelength-tunable optical parametric regenerators.

Low Penalty Uniformly Tunable Wavelength Conversion Without Spectral Inversion Over 30 nm Using SBS-Suppressed Low-Dispersion-Slope Highly Nonlinear Fibers

We demonstrate a simple and efficient cascaded operation of parametric wavelength conversion at 43 Gb/s by four-wave mixing for arbitrary input and output wavelengths over 30 nm, using SBS-suppressed low-dispersion-slope highly nonlinear fibers with a power penalty below 0.7 dB.

Counter-Dithering Pump Scheme for Cascaded Degenerate FWM Based Wavelength Converter

We demonstrate counter-dithering of pumps between two cascaded FWM processes for highly-efficient format-independent wavelength conversion. Up-to -1.2dB FWM conversion efficiency is obtained over 32-nm. 86-Gbps DP-QPSK are converted with OSNR penalty below 0.3dB at 10-3 BER.

Numerical modeling of the subwavelength phase-change recording using an apertureless scanning near-field optical microscope

The electromagnetic field enhancement (FE) at the end of the probe of an Apertureless Scanning Near-field Optical Microscope (ASNOM) is used to write nanometric dots in a phase-change medium. The FE acts as a heat source that allows the transition from amorphous to crystalline phase in a Ge2Sb2Te5 layer. Through the 2D Finite Element Method (FEM) we predict the size of the dot as a function of both the illumination duration and the incoming power density. Numerical results are found to be in good agreement with preliminary experimental data.

Parametric tunable dispersion compensation for the transmission of sub-picosecond pulses

Parametric tunable dispersion compensator (P-TDC), which allows format-independent operation owing to seamlessly wide bandwidth, is expected to be one of the key building blocks of the future ultra-high speed optical network. In this paper, a design of ultra-wide band P-TDC is presented showing that bandwidth over 2.5 THz can be achieved by compensating the chromatic dispersion up to the 4th order without employing additional method. In order to demonstrate the potential application of P-TDC in the Tbit/s optical time division multiplexing transmissions, 400 fs optical pulses were successfully transmitted through a dispersion managed 6-km DSF fiber span.

On the Cascadability of All-Optical Wavelength Converter for High-Order QAM Formats

With the evolution to ever more complex modulation formats for optical signals, all-optical wavelength converters offer great benefits to optical networks, thanks to the possibility of translating the wavelength of an optical signal regardless of its data rate or modulation format. To deliver its full advantages over conventional optical-electrical-optical conversion, an all-optical wavelength converter has to possess important features in terms of transparency, bandwidth, and cascadability for practical applications in real systems. In this paper, we review a recent development of an all-optical wavelength converter, which exhibits seamless conversion in the C-band with a low noise figure of 6.2 dB for dual-polarization (DP) phase-modulated signals. We then carry out an investigation by both experiment and calculation of the cascaded operation of the developed wavelength converter for high-order quadrature amplitude modulation (QAM) formats. A cascadability comparable to an erbium-doped fiber amplifier is achieved for DP-QPSK, DP-16QAM, and DP-64QAM signals, thanks to the exemplary characteristics of the wavelength converter.

0.2-dB gain excursion AGC-EDFA with a high speed VOA for 100-channel add/drop equivalent operation

We have developed a digitally controlled AGC-EDFA by combining an FF-controlled pump-LD and an FF-controlled VOA. We realized a gain excursion of less than 0.2 dB at a 100-channel add/drop equivalent operation.

Truly arbitrary wavelength conversion by cascaded four-wave mixing in low dispersion slope SBS suppressed highly nonlinear fibers

A simple and efficient cascaded operation of wavelength conversion for any arbitrary input and output wavelengths over 30 nm can be realized, using two dispersion-decreasing highly nonlinear fibers with SBS suppressed by distributed strain.

Plasmonic devices with controllable resonances--an avenue towards high-speed and mass fabrication of optical meta-materials.

We report on the fabrication of plasmonic devices with adjustable resonances in the visible portion employing a thermal lithography method. The genuine approach enables the fabrication of nanostructured pattern at a spatial resolution comparable to other nanofabrication techniques, but at significantly larger speeds and over extended spatial domains. The fabricated structures consisted in periodically arranged nanoholes in a silver thin film and supported localized plasmon resonance (LPR) in the vicinity of 370 nm. Results from measured spectral properties were in good agreement with simulations based on rigorous diffraction theory. The method was evaluated towards a potential application to realize large‐scale meta‐materials with effective negative refractive index in the visible.

Parametric node devices for extremely low-energy networks

Parametric processes in fiber have many intrinsic advantages for realizing all optical node functions necessary for the future dynamic optical path network that is potentially several orders of magnitude more efficient than todays network.