Photonic quantum computer by Ciro Santilli 32 Updated Created
Uses photons!
The key experiment/phenomena that sets the basis for photonic quantum computing is the two photon interference experiment.
The physical representation of the information encoding is very easy to understand:
  • input: we choose to put or not photons into certain wires or no
  • interaction: two wires pass very nearby at some point, and photons travelling on either of them can jump to the other one and interact with the other photons
  • output: the probabilities that photos photons will go out through one wire or another
Video 1.
Jeremy O'Brien: "Quantum Technologies" by GoogleTechTalks (2014)
Source. This is a good introduction to a photonic quantum computer. Highly recommended.