Narrow-Band Fiber-Coupled Single-Photon Source

A single-photon source is an essential tool for the emerging field of quantum technologies. Ideally, it should be spectrally compatible with other photonic devices while providing a high flux of narrow-band photons. The single organic dye molecule dibenzanthanthrene under cryogenic conditions possesses the given characteristics and therefore constitutes a prominent single-photon source. Nevertheless, the implementation of such a single-photon source requires a complex experimental setup involving a cryostat with a confocal microscope for the effective collection of the molecular emission. In the approach presented here we use a single emitter coupled directly to the end facet of an optical fiber. This has the potential to transfer a single-photon source based on a quantum emitter from a proof-of-principle type of setup to a scalable "plug-and-play" device. We present successful coupling of a single organic molecule to an optical fiber and record the excitation spectrum, measure the saturation curve, and analyze the contributions of Raman background fluorescence. The single-photon nature is proven by an antibunched autocorrelation recording, which reveals coherent Rabi oscillations.