Abstract

The scalability of high‑capacity networks increasingly depends on advances in switching technology. Optical switching, particularly using microring‑based logic, offers a path to higher bandwidth and lower signal degradation while enabling compact, cascadable architectures.
This thesis presents a microring modulator (MRM)‑based 2×2 optical switch built from cascadable optical logic gates (OLGs) with electronic control circuits. An OLG is a fundamental building block of optical computing systems, performing logic operations by manipulating optical signals rather than electrical ones, thereby leveraging the inherently higher speed and lower propagation loss of light. The OLG’s functionality is validated through experimental measurements of power transfer characteristics (PTC), optical noise margins (ONMs), and fan‑out performance. The 2×2 switch, implemented with seven interconnected OLGs, demonstrates the scalability of this approach for more complex optical logic networks.
To enable higher‑speed operation, a CMOS implementation of the electronic control circuit, for driving and processing optical‑logic signals, was designed and fabricated in TSMC's 65 nm technology, occupying an active area of 1 mm × 1.25 mm. The design incorporates a peak/low detector‑based offset compensation technique that ensures stable performance under unbalanced input data patterns.
Post-layout simulations verify correct logic functionality, showing a simulated propagation delay of approximately 107 ps. Despite this delay, the standalone gate can process narrow pulses, corresponding to a data throughput of up to 8 Gbps.
The combined demonstration of discrete and integrated implementations highlights the potential of microring‑based optical switching as a scalable solution for future high‑performance networking and computing systems.