Single organic molecules as building blocks for photonics

Single organic molecules can not only generate single photons, but also be used as basic building blocks to manipulate light in photonic circuits. A molecule can, for example, attenuate a laser beam, act as a phase shifter or be used as an optical transistor. The principle behind these remarkable functionalities is the strong interaction of focused light with quantum emitters such as atoms, quantum dots, color centers, or molecules, whereby the latter offer exceptional opportunities. Experiments have reached a level where single molecules can communicate with each other using single photons.