Optical photonics-based quantum computers
Optical photonics is a fascinating branch of physics that deals with optical photons, which are chargeless particles responsible for the phenomenon of light. It is because of optical photons that we are able to see the world around us. As well as this, these photons have been used in optical fibers for many years to enable high-speed internet connections and better network connectivity. It turns out that these same photons can be used to perform quantum computations as well!
Figure 4.6 shows a quantum operation using optical equipment for quantum computation. BS refers to the beam splitter, which is used to split a light beam into two parts. The phase shifter used is non-linear in nature and introduces delays or advances in the phase of the laser signal used here:
In the preceding figure, you can see that the beam splitter is used to create the Hadamard gates...