INTEGRATED circuits that process optical signals are just too large. Now a team at the Massachusetts Institute of Technology have worked out how to miniaturise them.
The team has been working with photonic crystals that work by trapping light in tiny three-dimensional channels carved into their crystal structure. These channels are roughly the same size as the wavelength of light they are designed to carry. But to process signals as well as carry them, the circuits must contain active devices such as lasers and switches that can alter optical signals, and these have proved difficult to create on this scale.…
