Solid‐state quantum emitters

This perspective gives a tutorial overview of the development of solid-state quantum emitters over the past three decades, focusing on the key parameters that are used to assess their performance for applications in quantum photonics. Specifically, it covers single-photon purity and indistinguishability, source brightness, and on-demand operation. The perspective includes a brief comparison of different material systems and concludes with a discussion of challenges that remain to be solved.