Single-photon source

A single-photon source is a device that produces one photon of light at a time. It works by taking a particle of light (called a photon) and splitting it into two. Then each photon is sent out separately in a beam of light. This means that each time the device is used, it produces one photon instead of many. Single-photon sources are used by scientists and researchers to study things that need to be measured very closely, since they can be sure that they only get one photon when they use it.