Abstract
The efficient generation of single and entangled photons represents a major technological challenge for many applications, from communications to quantum computers. In this lecture, we present two main approaches to the generation of single photons. The first exploits nonlinear optics, the second single atoms whose spontaneous emission process is controlled. We will describe the advantages and challenges of each method, their implementation in integrated systems and the current state of the art. We will then present the approaches adopted for the generation of entangled photons and increasingly complex states of light.
