4.6 Opportunities for Optics in Integrated Circuits Applications

Optics brings opportunities for addressing two key problems in electronic chips and systems – interconnects and timing. Optics in principle enables dense, high-speed, long lines and solves prob-lems of signal integrity (e.g., crosstalk, reflections, and voltage isolation) [1]; opportunities for off-chip interconnects are grow-ing, and on-chip possibilities pose key questions [2]. Optical back-planes are under commercial development, and research shows promise for dense off-chip interconnects with hybridized lasers and modulators. Optics also allows radical concepts such as short pulse interconnects [3], with timing, sensitivity and latency enhancements, and wavelength division multiplexing [4], with higher line densities and ultimate compatibility with optical net-works. All of these radical concepts have now seen laboratory demonstrations [3,4]. Short pulse optics offers many opportunities for precise timing, a