Silicon Photonics Expanding into Cryogenics, and the Future of Optical Interconnects

Abstract

Significant advances in silicon photonics over the last two decades have led to a wide array of robust photonic devices that have found many applications including in telecommunications. Despite these advances, the cost of optical interfacing (packaging) of photonic integrated circuits (ICs) makes up the bulk of the manufacturing cost of these chips. In this dissertation, I will present my research in developing compact, efficient and low-cost adiabatic couplers that can enable lower-cost and higher-throughput manufacturing of photonic ICs. I will also present a novel method for designing compact, highly efficient and high misalignment tolerance multi-segment couplers for chip-to-chip connectivity. This technology was also extended to ion-exchange glass waveguides which can provide a platform for more efficient chip-to-chip communication and more economical integration of photonic and electronic components. I will further demonstrate electro-optic modulation using silicon micro-disk modulators and wavelength division multiplexing at cryogenic temperatures which is pivotal to the advancement of cryogenic computing systems including cryogenic supercomputers of the future.