Optoelectronic interconnects in VLSI: the reality of digital optical computing?

The relative strengths of optical and electronic technology are discussed with a view to identifying the optimum mix applicable at the discrete logic gate or chip level. It is proposed that an optimum high-speed processor should be partitioned into synchronous electronic islands, interconnected by optics. The use of free-space optical wiring and its limitations are discussed. The characteristics required of optoelectronic interfaces are delineated. A self-routing switching matrix is considered as a test case for the hybrid optoelectronic approach. By partitioning the complex self-routing circuit in the manner described, all the electrical pathways are very nearly equalized, favoring very-high-bit-rate operation. Information flow is also very streamlined.>