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We demonstrate a method of minimizing the wavelength sensitivity of the all-optical bit-pattern recognition relying on a passive optical correlator. We accomplish all-optical 40-Gb/s, 8-bit pattern recognition with much reduced wavelength sensitivity by combining a wavelength converter front-end and a passive optical correlator.

The performance of optical logic such as XOR is analyzed by solving rate equations of quantum dot SOA. Results show SOA with quantum dots active region can greatly increase the operation frequency limiting regular SOAs.

We present a compact reconfigurable 8-bit optical matching filter fabricated using 4% delta high-index-contrast silica-on-silicon waveguides. We demonstrate its working by successfully correlating 8-bit binary phase-shift keyed patterns.

We demonstrate a stable dual-wavelength actively mode-locked erbium-doped fiber laser operating at 20 GHz. The pulses have been stabilized using a phase locked loop. Dual wavelength pulse trains with pulse widths ~ 3ps are obtained.

80 Gb/s All-optical XNOR has been demonstrated using four wave mixing scheme in highly nonlinear fibers. The nonlinear Schrodinger equations (NLS) describing the process in fibers has been simulate and solved using split-step Fourier method.

We demonstrate a stable dual-wavelength actively mode-locked erbium-doped fiber laser operating at 20GHz. We use a highly nonlinear fiber in the optical cavity. Simultaneous dual wavelength pulse trains with pulse widths ~ 1ps are achieved.

The characteristics of both semiconductor colliding pulse mode locked lasers and mode locked fiber lasers are described. Optical pulses with few ps pulse width at varying repetition rates have been obtained using rational harmonic mode locking technique. A scheme for stable pulse train output from fiber lasers is described.

All Optical Add/Drop which includes optical demultiplexng are important for real-time transmission of high data rates to end users, specifically when access to subsets of a high bit rate data stream is required, for data processing, or to add and drop data channels.

We present quantitative comparisons of three categories of velocity estimation algorithms including centroid techniques (adaptive centroid technique and weighted centroid technique), sliding-window filtering technique, and correlation techniques (autocorrelation and cross-correlation). We introduce, among these five algorithms, two new algorithms: weighted centroid and sliding- window filtering. Simulations and in vivo blood flow data are used to assess the velocity estimation accuracies of these algorithms. The comparison demonstrates that the sliding-window filtering technique is superior to the other techniques in terms of velocity estimation accuracy and robustness to noise.

All optical XOR functionality is demonstrated experimentally using a an integrated SOA-based Mach-Zehnder interferometer at 40 Gb/s. Further, a differential scheme for XOR operation is experimentally investigated in order to reach higher speeds.

Optical coherence tomography (OCT) is a new technique for various medical-imaging applications. The operation is based on a Michelson interferometer with a low coherence source. We have constructed a prototype system designed for imaging periodontal tissues.

The monolithic integration of optical and electronic components on the same substrate permits higher speed and more stable operation of the systems that they comprise. Optoelectronic integrated circuits (OEICs) are the objects of intense research, and many improvements in their performance have been reported in the literature in both the InP and GaAs systems. Of particular interest have been monolithic photoreceivers and optical transmitters. We present data on the successful operation of both integrated-optical receivers and transmitters suitable for use in wide-bandwidth optical transmission systems.

We report the fabrication and performance characteristics of InGaAsP double-channel planar buried heterostructure (DCPBH) lasers with multi-quantum well (MQW) active layers emitting near 13 μm. The lasers have a threshold current of ~30 mA at 30°C and external differential quantum efficiencies of ~50% at 30°C. The lasers operate in a single transverse mode up to high powers (>10 mW/facet) and can be modulated at high bit rates (~2 Gbit/sec).