The evolving needs of network carriers are changing the design of optical networks. In order to reduce cost, latency, and power consumption, electrical switches are being replaced with optical switching fabrics at the core of the networks. An example of such a network is an Agile All-Photonic Network (AAPN). / This thesis presents a novel device that was designed to operate as an optical switch within the context of an AAPN network. The device is a Reprogrammable Optical Phase Array (ROPA), and the design consists of applying multiple electric fields of different magnitudes across an electro-optic material in order to create a diffractive optical element. The configuration of the electric fields can change to modify the properties of the diffractive device. / Such a device has a wide range of potential applications, and two different ROPA designs are presented. Both designs are optimized to function as 1xN optical switches. The switches are wavelength tunable and have switching times on the order of microseconds. The ROPA devices consist of two parts: a bulk electro-optic crystal, and a high-voltage CMOS chip for the electrical control of the device. The design, simulation, fabrication and testing of both the electrical and optical components of the devices are presented.

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This thesis studies and mathematically models nonlinear interactions among channels of modern high bit rate (amplitude/) phase modulated optical systems. First, phase modulated analogue systems are studied and a differential receiving method is suggested with experimental validation. The main focus of the rest of the thesis is on digital advanced modulation format systems. Cross-talk due to fiber Kerr nonlinearity in two-format hybrid systems as well as 16-QAM systems is mathematically modelled and verified by simulation for different system parameters. A comparative study of differential receivers and coherent receivers is also given for hybrid systems. The model is based on mathematically proven assumptions and provides an intuitive analytical understanding of nonlinear cross-talk in such systems. / Graduate

Wavelength Division Multiplexing Passive Optical Networks (WDM PONs) offer a great solution to satisfy the increasing demand of bandwidth. In addition, it offers a higher level of data security through virtual point to point connections. A great challenge in realizing cost-effective WDM PON is the need for a transmitter at each Optical Network Unit (ONU) with a dedicated wavelength, which overloads the total cost of the system, in addition to reducing the number of available wavelengths in the system. Remodulation scheme is an ultimate solution for these problems of WDM PONs as the downstream signal itself is remodulated with upstream data which saves the need for a laser source at the ONU side. In this thesis I propose and experimentally demonstrate a novel wavelength remodulation scheme for WDM PONs that employs Differential Phase Shift Keying (DPSK) for downstream and Return to Zero DPSK (RZ-DPSK) for upstream. The use of DPSK enhanced the system with improved receiver sensitivity and RZ-DPSK improved the tolerance toward chromatic dispersion. In addition, I investigate the Backreflection (BR) penalty resulting from beat noise of BRs with upstream signal in a bidirectional WDM PON system that uses remodulation and phase modulation as a modulation format. I experimentally demonstrate the optimal conditions to operate the system and minimize the BR penalty.

Today s supercomputers require interconnection networks with high bandwidth and low latency to exploit parallelism. The data vortex is an all optical path interconnection network defined and then proven to achieve high level of message acceptance and low levels of message latency. In this thesis research, three enhancements to the data vortex are defined and tested for performance. They are compared to an unmodified data vortex using the average latency and offered traffic acceptance rates as metrics. Minimal angle counts are established where express lane enhancements are established. An express lane enhancement allows exploitation of locality yielding an 8% to 12 % reduction in average latency and a 4% to 6% increase in message acceptance. Semi-Express lanes cannot effectively exploit locality but still yield a 20% increase in message acceptance and a 4% decrease in average latency. Express outputs can exploit locality for a 28% to 32% increase in message acceptance and 12% to 15% decrease in average latency.

In this thesis, the development of a novel electro-thermally actuated bi-stable out-of-plane two way actuated buckled micro-bridge for a potential application in optical switching is presented. The actuator consists of a bridge supported by 'legs' and springs at its four corners. The springs and the bridge are made of a tri-layer structure comprising of 2.5??m thick low-stress PECVD oxide, 1??m thick high-stress PECVD oxide and 2??m thick heavily phosphorus doped silicon. The legs, on the other hand, are 2??m thick single layer heavily phosphorus doped silicon. Both legs and springs provide elastically constrained boundary conditions at the supporting ends, without of which important features of the micro-bridge actuator could not have been achieved. This microbridge actuator is designed, simulated using ANSYS, fabricated and tested. The results from the testing have shown a good agreement with analytical prediction and ANSYS simulation. The actuator demonstrated bi-stability, two-way actuation and 31??m out-of-plane movement between the two-states using low voltage drive. Buckled shape model, design method for bi-stability and thermo-mechanical model are developed and employed in the design of the micro-bridge. These models are compared with Finite Element (FE) based ANSYS simulation and measurements from the fabricated micro-bridge and have shown a good agreement. In order to demonstrate the potential application of this actuator to optical switching, ANSYS simulation studies have been performed on a micro-mirror integrated with the micro-bridge actuator. From these studies, the optimum micro-mirror size that is appropriate for the integration has been obtained. This optimal mirror size ensures the important features of the actuator. Mirror fabrication experiments in (110) wafer have been carried out to find out the appropriate compensation mask size for a given etch depth and the suitable wafer thickness that can be used to fabricate the integrated system.