Micro/Nano/Quantum-Scale VLSI Photonics : Issues, Challenges, and Prospects

초록

This paper presents an overview of our study on the subject of what we categorically term "VLSI(very large scale integrated) microphotonics." "VLSI microphotonics" is a critically important area to open up the "21th century photonic age" and, as such, faces an enormous challenge as the "VLSI microelectronics" did in the "20th century electronic age." In principle, "VLSI microphotonics" is geared to the concept of utilizing space division, but broadly it requires diverse disciplines of study to be brought together for its success as "VLSI microelectronics" did in the 20th century. It can offer advantages of making devices and systems light, compact, low-powered, and multi-functional for high performance operation. However, as the photons have fundamentally different properties from the properties of electrons, the nature of "VLSI microphotonics" will be very much different from that of the "VLSI microelectronics." New physics, new materials, new diveces, new circuits and, therefor, new functions will need to be explored. We will approach the "VLSI microphotonics" in three essential but closely linked steps of miniaturization, interconnection, and integration as in microelectronics. First, in miniaturization, we will need to challenge how small the devices can be and what determines the miniaturization. The issues include the size effect, proximity effect, microcavity effect, optical interference effect, high field effect, nonlinear effect, quantum optical effect, and noise effect. Sencondly, in interconnection, we will need to challenge the issues of connecting and couplings small devices, either identical (homogeneous interconnection) or non-identical (heterogeneous interconnection). Optical interconnection between devices, minimizing interconnection losses, and maintaininng optical modes between miniaturized devices, are to be considered. Thirdly, in integration, we will need to challenge the issues of how densely the devices can be integrated. The issues include t