Single photon flips optical transistor – sort of

It’s still a long way from a light-based computer, but researchers from IBM Research and Skolkovo Institute of Science and Technology have at least provided a glimpse of what such systems could look like. They developed an ‘optical transistor’ that switches up to a thousand times faster than CMOS transistors, requiring only the energy of a single photon to change state.

The device consists of a 35-nanometer-thin sheet of an organic semiconducting polymer, sandwiched between two inorganic ‘mirrors.’ Light introduced inside this microcavity gets trapped, maximizing its interaction with the polymer.