Monitoring and automatic tuning and stabilization of a 2×2 MZI optical switch for large-scale WDM switch networks.

Large-scale optical switch networks employ wavelength division multiplexing to expand and facilitate multiple input and outputs. Such networks can be implemented with the Mach-Zehnder interferometer (MZI) as the building block. A fully-loaded MZI switch, meaning one with two optical signals at its two inputs and one that is capable of simultaneously switching those inputs to its two outputs, reduces the number building blocks within the network, and as a result makes them more power and area efficient. However, for practical operation, such MZI switches need to be automatically controlled for overcoming fabrication and thermal variations. We present an interference-based monitoring method that enables automatically switching, tuning, and stabilizing of a fully-loaded 2×2 MZI optical switch and demonstrate a prototype on an SOI platform. Using the proposed device and off-the-shelf electronics, we demonstrate automatic tuning and stabilization of an MZI switch with 12.5 Gb/s and 25 Gb/s data rates and channel spacing as small as 1 nm.

Optomechanics for a four-stage hybrid-self-electro-optic-device-based free-space optical backplane.

We present the design, fabrication, and testing of optomechanics for a free-space optical backplane mounted in a standard 6U VME backplane chassis. The optomechanics implement an optical interconnect consisting of lenslet-to-lenslet, as well as conventional lens-to-lens, links. Mechanical, optical, electrical, thermal, material, and fabrication constraints are studied. Design trade-offs that affect system scalability and ease of assembly are put forward and analyzed. Novel mounting techniques such as a thermal-loaded interference-fitted lens-mounting technique are presented and discussed. Diagnostic tools are developed to quantify the performance of the optomechanics, and experimental results are given and analyzed.

Design, implementation, and characterization of an optical power supply spot-array generator for a four-stage free-space optical backplane.

The design and implementation of a robust, scalable, and modular optical power supply spot-array generator for a modulator-based free-space optical backplane demonstrator is presented. Four arrays of 8 x 4 spots with 6.47-mum radii (at 1/e(2) points) pitched at 125 mum in the vertical direction and 250 mum in the horizontal were required to provide the light for the optical interconnect. Tight system tolerances demanded careful optical design, robust optomechanics, and effective alignment techniques. Issues such as spot-array generation, polarization, power efficiency, and power uniformity are discussed. Characterization results are presented.

Perfect-shuffle interconnected bitonic sorter: optoelectronic design.

The algorithmic, electronic, and optical aspects of the implementation of a perfect-shuffle interconnected bitonic sorter are analyzed. The performance metrics such as the bit output data rate and the power consumption of the system are quantified. The sorting module is designed to demonstrate the parallel nonlocal interconnection of smart-pixel arrays and the use of optical-image control masks in a functioning information processor.