The technology of modern purely electrical computers requires more electrical wiring for intra-chip and inter-chip communications as the number of cores increases. Consequently, energy consumption increases due to heat dissipation from low bandwidth electric wires. The conversion of electrical signals to optical signals has been proposed in the future electro-optical computers as a way of addressing this issue. Much work has gone into the design, fabrication, and testing of components of new optical elements that can be implemented in chips fabricated in unmodified CMOS processes.
Besides other advances achieved in the Ph.D. thesis, in the thesis defense only the chapter about a novel electronically-controlled optical switch with free-carrier injection, which can switch digital optical signals from one waveguide into other, will be presented. This switch is many times smaller, faster and more energy efficient than the optical switch based on a traditionally used Mach-Zehnder interferometer.
Thesis Supervisor: Professor Peter Hagelstein