Bright and Polarized Fiber In-Line Single-Photon Source Based on Plasmon-Enhanced Emission into Nanofiber Guided Modes

We demonstrate a bright and polarized fiber in-line single-photon source based on plasmon-enhanced emission of colloidal single quantum dots into an optical nanofiber. We show that emission properties of single quantum dots can be strongly enhanced in the presence of single gold nanorods leading to a bright and strongly polarized single-photon emission. The single photons are efficiently coupled to guided modes of the nanofiber and eventually to a single-mode optical fiber. The brightness (fiber-coupled photon count rate) of the single-photon source is estimated to be 12.2±0.6 MHz, with high single-photon purity [g2(0)=0.20±0.04] and degree of polarization as high as 94-97 %. The polarized and fiber-coupled single photons can be implemented for potential applications in quantum photonics.