Photon Information Processing

Since the advent of the electronic transistor in 1947 at Bell Laboratory, human history has been phase shifted from the industrial era toward the information era. Since the internet opened in the 1990s, anyone has virtually been able to access anybody anytime, anywhere. Unfortunately, due to the limits on the speeds of electronic devices, the so-called “end of Moor’s law,” the electronic evolution has already come to an end. To make a quantum jump toward a ubiquitous society in the future, many researchers have studied photon information processing over the last several decades. However, most studies have been limited by less-matured technologies. Here, strong photon candidates that can compete with electronic gadgets and allow human civilization to continue its progress are reviewed.