Controlling Light on a Superconducting Chip
It may not be soon, but one day we will have superconducting computer chips within quantum computers, driving the most complex algorithms man has created. There is still a great deal of research to be done before that can become a reality though, but thankfully it is being done. Researchers at the University of California, Santa Barbara have recently built a superconducting chip with a useful feature; a superconducting switch.
While superconductors are most often associated with electrons, as the particles will flow without resistance along them, in this chip the superconductors were used to control photons, the quanta of light. To capture and hold photons, the researchers built a superconducting cavity and connected to it a superconducting switch. This switch could be opened and closed faster than the lifetime of a photon within a cavity and could also be left open indefinitely, like a shutter.
What makes the incorporation of the switch so important is that for the chip to be useful, it must be possible to send a single bit of data of a time, and no more, which is accomplished by closing the switch at the right time. The next step for this technology is to develop a way transfer photons between two cavities over a distance, with the ultimate goal being a reliable means to send a photon from Earth to an orbiting satellite.