Guest Editorial Optical Interconnects
Journal of Lightwave Technology
D EMAND for short distance optical interconnects is growing rapidly due to the rise of mega data centers and the continuing increase in high performance computing performance. While VCSEL-based interconnects have previously dominated this space, increasing interconnect distances and performance demands have broadened the technologies of interest, motivated increased integration levels, and introduced key challenges which industry and academia must address. This special issue of the IEEE/OSA
... NAL OF LIGHTWAVE TECHNOLOGY on OPTICAL INTERCONNECTS, which features expanded versions of key papers presented at the IEEE Optical Interconnects Conference in April 2015, covers a wide array of leading edge technologies and research in network systems, architectures, applications, subsystems, and devices. The special issue includes eight invited papers on highperformance optical interconnect architectures and key technologies which can support the rising bandwidth demands of mega data centers and high-performance computing systems. An optical interconnect architecture capable of supporting 1PFlops performance is described in the paper from Schwetmann et al. As optical switches provide the potential for dynamic resource allocation and real-time routing, Chen et al. explore the dynamic control of data signals through a silicon photonic switch matrix and demonstrate a programming interface for configuring the switch. Two papers discuss novel silicon photonic modulator devices, including an ultra-small silicon optical modulator based on a node-matched-diode geometry from Kupijai et al. and a compact optical modulator based on an EO polymer filled silicon slot photonic crystal waveguide from Zhang et al. At the receive-side, a low-power high-sensitivity CMOS/silicon photonic receiver front-end is presented in the paper from Saeedi et al. As microring-resonator based silicon photonic interconnect architectures provide the potential for compact WDM interconnects, Jayatilleka et al. analyze the key issues of demultiplexer crosstalk, channel spacing, and maximum aggregate data rate. VCSEL-based links with varying degrees of receiver-side equalization complexity are investigated for short reach optical interconnects in the paper by Karinou et al. On-board optical interconnects are also addressed in the paper by Chen et al. who present studies that show the potential for 100 Gb/s over multimode polymer waveguides. Seven contributed papers also reflect the wide variety of topics covered in the IEEE Optical Interconnects Conference. A broad mix of papers span from high-throughput compute nodes with optical interconnects, design space exploration of silicon photonic interconnects, transceiver technology, device opto-electronic co-simulation models, and high-capacity optical packaging. The guest editors wish to thank the authors for contributing their papers and meeting the tight deadlines required for the Special Issue. They also thank many anonymous reviewers whose feedback and comments ensure the high quality of the Journal, the JLT Editor-in-Chief P. Winzer for his guidance, and finally D. Hargis, publication co-ordinator, for putting this issue together. We hope that this JLT Special Issue will provide a useful cross section of the state-of-the-art in optical interconnects. With the ever growing data processing and transmission demands from cloud computing, video streaming, and Internet of Things (IoT) applications, it is a very exciting time to be involved in the area of optical interconnects!