J.M. Martinez

IST-LASAGNE: towards all-optical label swapping employing optical logic gates and optical flip-flops

The Information Society Technologies-all-optical LAbel SwApping employing optical logic Gates in NEtwork nodes (IST-LASAGNE) project aims at designing and implementing the first, modular, scalable, and truly all-optical photonic router capable of operating at 40 Gb/s. The results of the first project year are presented in this paper, with emphasis on the implementation of network node functionalities employing optical logic gates and optical flip-flops, as well as the definition of the network architecture and migration scenarios.

All-optical flip-flop based on a single SOA-MZI

A novel architecture of an all-optical flip-flop is proposed. The architecture is comprised of a single semiconductor optical amplifier-based Mach-Zehnder interferometer with a feedback loop. The simulation results show that low switching energies (<2-pJ pulses) and fast operation (<1-ns response delays) may be achieved.

Optically beamformed beam-switched adaptive antennas for fixed and mobile broad-band wireless access networks

In this paper, a 3-bit optical beamforming architecture based in 2/spl times/2 optical switches and dispersive media is proposed and demonstrated. The performance of this photonic beamformer is experimentally demonstrated at 42.7 GHz in both transmission and reception modes. The progress achieved for realizing these architectures with integrated optics is also reported. Due to its advanced features (i.e., potential fast-switching, huge bandwidth, and immunity to electromagnetic interference), the architecture is a very promising alternative to traditional beamforming technologies for implementing beamformed base-station antennas in fixed and mobile broad-band wireless access networks operating in the millimeter-wave band. The study presented here has been carried out in the frame of the IST 2000-25390 OBANET project.

From IP over WDM to all-optical packet switching: economical view

In this paper, a technoeconomical study of several (optical) packet-switching node architectures is described. Therefore, different architectures proposed in IST-WASPNET and IST-LASAGNE projects as well as a standard optical circuit switching approach are considered, and their economical impact is estimated by means of cost comparisons between the different technologies. The switching architectures all use optical fiber as a transport medium, but each of them uses a different technology to process switching. Their cost is evaluated as a function of most characteristic parameters for each technology. In the all-optical approaches, the main cost is that related to the fiber assembly, whereas for electronic processing, the most expensive cost is related to the optical-electronic-optical (OEO) conversions. The results show that the integration of optical components is crucial to make all-optical packet-switching nodes feasible.

All-optical network subsystems using integrated SOA-based optical gates and flip-flops for label-swapped networks

In this letter, we demonstrate that all-optical network subsystems, offering intelligence in the optical layer, can be constructed by functional integration of integrated all-optical logic gates and flip-flops. In this context, we show 10-Gb/s all-optical 2-bit label address recognition by interconnecting two optical gates that perform xor operation on incoming optical labels. We also demonstrate 40-Gb/s all-optical wavelength-switching through an optically controlled wavelength converter, consisting of an integrated flip-flop prototype device driven by an integrated optical gate. The system-level advantages of these all-optical subsystems combined with their realization with compact integrated devices, suggest that they are strong candidates for future packet/label switched optical networks

All-optical address recognition scheme for label-swapping networks

A two-bit all-optical correlator based on cascaded logic XOR gates is demonstrated with 10-Gb/s optical labels. Error-free operation with 13-dB extinction-ratio performance is achieved after the second stage by adjusting the label signal input power. The signal degradation at the device output is mainly caused by the accumulated amplified spontaneous emission noise from each active Mach-Zehnder interferometer. The experimental results show the feasibility of this architecture to perform address-recognition functionalities in photonic routers.

All-optical packet routing scheme for optical label-swapping networks

A novel scheme for all-optical label reading and packet routing is proposed. The architecture is comprised of all-optical logic XOR gates and all-optical flip-flops based on single Mach-Zehnder interferometers incorporating semiconductor optical amplifiers (SOA-MZIs). The simulation results show that a very small penalty (less than 0.45 dB) for 10 Gbit/s packet processing can be achieved.

10 Gb/s Reconfigurable Optical Logic Gate Using a Single Hybrid-Integrated SOA-MZI

Abstract A novel reconfigurable Boolean device based on a single Mach-Zehnder interferometer with semiconductor optical amplifiers is demonstrated at 10 Gb/s using intensity return-to-zero modulated signals. The experimental results show that the device can be dynamically reconfigured to operate as a logic XOR, AND, OR, and NOT gate using optical switches. By properly adjusting the input powers, an extinction ratio higher than 10 dB may be obtained. The potential of integration of this architecture makes it an interesting approach in photonic computing and optical signal processing.

Solar energy harvesting in photoelectrochemical solar cells

Here we study different approaches for increasing energy harvesting in titania based photoelectrochemical solar (PES) cells. We study the light harvesting of PES cells when photonic crystal and photonic sponge architectures are used. We also report on the influence of the surface corrugation of the metal electrode on the harvesting of photocarriers in solar cells

All-Optical Processing Based on a Logic xor Gate and a Flip-Flop Memory for Packet-Switched Networks

The routing functionality by all-optically interconnecting semiconductor-based all-optical logic gates and flip-flops is demonstrated in the frame of an all-optical label swapping (AOLS) network. We experimentally show that the output of the all-optical 2-bit correlator is capable of toggling the states of the integrated flip-flop every 2.5 ns via an adaptation stage. High extinction ratios are obtained at the output of the flip-flop, which can be used to feed a high-speed wavelength converter to complete the routing functionality of the AOLS node. The potential integration of these semiconductor optical amplifier integrated Mach-Zehnder interferometer-based devices make the proposed approach a very interesting solution for future packet switched optical networks.