What’s silicon photonics?
An integrated circuit (IC) is a collection of electronic circuits on a tiny piece of silicon. A large number of these are put together to create a chip, which we see in pretty much every electronic device today. Electronics have become an integral part of our lives, to the point at which we are fully dependent on them for most of our work — some of us will be unemployed, or in a different field, if they weren’t as accessible as they are now. To keep up with the demand for better performance every generation, ICs needed to be miniaturized more and more to fit more ICs in a chip. In fact, an observation was made by Gordon Moore, and coined the Moore’s Law, that the number of transistors in an integrated circuit (IC) doubles about every two years. But we are at the point where we are at our limit of how small we can make our transistors.
The question now becomes: How do we take our chips to the next level, beyond the Moore concept, and also overcome some of traditional ICs’ limitations such as heat generation?
In comes the photonic integrated circuit — an IC that runs largely on light. A photonic integrated circuit (PIC) takes in light injected via a laser and transmits optical signals through a set of photonic devices. Photonic devices can include waveguides (which are akin to wires in electronics), couplers, etc. PICs use less power, generate less heat, and can be fabricated with the same tools that are used for regular ICs, while still performing better than and in tandem with them.
