Parametric fluorescence in periodically poled silica fibers

We report the observation of quasiphase matched parametric fluorescence fro m a periodically poled silica fiber. A pair-photon production rate of more than 100 MHz around 1532 nm was achieved in second-order nonlinear gratings for 300 mW of pump power at 766 nm. These results are very promising for t he realization of reliable all-fiber single-photon sources for quantum cryp tography systems and metrology applications. (C) 1999 American Institute of Physics. [S0003-6951(99)03442-7].