The science of how light interacts with matter is called quantum electrodynamics or QED and the theory on which it is based is one of the crowning achievements of 20th century physics.
Today, it lies at the heart of an emerging technology called circuit-QED, in which photons trapped on a silicon chip are made to interact with superconducting devices called artificial atoms, which have various energy levels just like real atoms.
This is a promising tool for quantum computation. Circuit-QED devices manipulate quantum information as it is transferred from light to matter and vice versa. And the fact that this all takes place on a single chip allows unprecedented control.
via Technology Review
