Dimitrios Petrantonakis

Optical Static RAM Cell

We demonstrate an optical static random access memory cell that provides read and write functionality at 5 Gb/s. The circuit comprises a hybridly integrated semiconductor optical amplifier-Mach-Zehnder interferometer (SOA-MZI) flip-flop serving as the memory unit and two additional SOA-based cross-gain modulation switches for controlling access to the memory cell.

40 Gb/s NRZ Wavelength Conversion Using a Differentially-Biased SOA-MZI: Theory and Experiment

We present theoretical and experimental performance analysis of 40 Gb/s Non-Return-to-Zero (NRZ) All-Optical Wavelength Conversion (AOWC) using a differentially-biased SOA-MZI. A frequency domain transfer function model for both the standard single-control SOA-MZI-based AOWC and for the differentially-biased SOA-MZI is analytically derived, exploiting first order perturbation theory techniques and showing that only the differentially-biased scheme can yield an almost flat low-pass filtering response enabling wavelength conversion at 40 Gb/s. The theoretically obtained results are also confirmed through experiments that demonstrate successful 40 Gb/s AOWC functionality for NRZ data signals only when a differentially-biased SOA-MZI configuration is employed, whereas an error-floor is obtained when 40 Gb/s NRZ AOWC with the standard single-control SOA-MZI scheme is attempted. The 1.7 dB negative power penalty obtained by the differentially-biased SOA-MZI architecture confirms its enhanced regenerative properties and its potential for extending 40 Gb/s optical transparent network dimensions by means of cascaded 2R AOWC stages.

A 40 Gb/s 3R Burst Mode Receiver with 4 integrated MZI switches

We demonstrate for the first time a 40 Gb/s all-optical 3R burst-mode receiver error-free operation for 9,3 dB power fluctuation between short bursty packets. It consists of a sequence of four integrated MZI switches.

40 Gb/s 2R Burst Mode Receiver with a single integrated SOA-MZI switch.

We demonstrate a novel scheme for 2R burst mode reception capable of operating error-free with 40 Gb/s variable length, asynchronous optical data packets that exhibit up to 9 dB packet-to-packet power variation. It consists of a single, hybrid integrated, SOA-based Mach-Zehnder Interferometer (SOA-MZI) with unequal splitting ratio couplers, configured to operate as a self-switch. We analyze theoretically the power equalization properties of unequal splitting ratio SOA-MZI switches and show good agreement between theory and experiment.

Optical-Logic-Gate Aided Packet-Switching in Transparent Optical Networks

The objective of this research is to propose two new optical procedures for packet routing and forwarding in the framework of transparent optical networks. The single-wavelength label-recognition and packet-forwarding unit, which represents the central physical constituent of the switching node, is fully described in both cases. The first architecture is a hybrid opto-electronic structure relying on an optical serial-to- parallel converter designed to slow down the label processing. The remaining switching operations are done electronically. The routing system remains transparent for the packet payloads. The second architecture is an all-optical architecture and is based on the implementation of all-optical decoding of the parallelized label. The packet-forwarding operations are done optically. The major subsystems required in both of the proposed architectures are described on the basis of nonlinear effects in semiconductor optical amplifiers. The experimental results are compatible with the integration of the whole architecture. Those subsystems are a 4-bit time-to-wavelength converter, a pulse extraction circuit, a an optical wavelength generator, a 3times8 all-optical decoder and a packet envelope detector.

Packet clock recovery using a bismuth oxide fiber-based optical power limiter

We demonstrate an optical clock recovery circuit that extracts the line rate component on a per packet basis from short data packets at 40Gb/s. The circuit comprises a Fabry-Perot filter followed by a novel power limiting configuration, which in turn consists of a 5m highly nonlinear bismuth oxide fiber in cascade with an optical bandpass filter. Both experimental and simulation-based results are in close agreement and reveal that the proposed circuit acquires the timing information within only a small number of bits, yielding a packet clock for every respective data packet. Moreover, we investigate theoretically the scaling laws for the parameters of the circuit for operation beyond 40 Gb/s and present simulation results showing successful packet clock extraction for 160 Gb/s data packets. Finally, the circuits potential for operation at 320 Gb/s is discussed, indicating that ultrafast packet clock recovery should be in principle feasible by exploiting the passive structure of the device and the fsec-scale nonlinear response of the optical fiber.

Four-Wavelength 3R Burst Mode Regenerator Using Three Integrated Quad MZI Arrays

We demonstrate an all-optical four-wavelength 3R burst mode regenerator, operating error-free with variable length data packets that exhibit 6-dB packet-to-packet power variation. The circuit was implemented using a sequence of three integrated quad MZI arrays.

Optically-Addressable Packet Timeslot Interchanger Using a Quadruple Switch Array

We propose and demonstrate a wavelength converter-based time-slot-interchanger architecture consisting of cascaded programmable delay stages. It uses an integrated quadruple switch array of HMZI switches and operated error-free with 10 Gb/s NRZ packets.

Packet-level synchronization scheme for optical packet switched network nodes

We demonstrate an all-optical, self-synchronization scheme for optical packet switched network nodes. It provides both the packet clock signal and the packet beginning, marker pulse. The circuit uses two hybridly integrated MZI switches and has been evaluated with synchronous, asynchronous and variable length, data packets at 10 Gb/s. It is compact and requires relatively low energies to operate.

40 Gb/s NRZ wavelength conversion with enhanced 2R regeneration characteristics using a differentially-biased SOA-MZI switch

We present error-free 40 Gb/s NRZ signal wavelength conversion with a differential biasing scheme in a SOA-Mach Zehnder interferometer. Experimental performance analysis shows 1.7 dB negative power penalty and enhanced 2R regenerative characteristics.