  We experimentally demonstrate, for the first time to our knowledge, the
generation of correlated photon pairs in a liquid-core photonic crystal fiber.
Moreover, we show that, thanks to the specific Raman properties of liquids, the
Raman noise (which is the main limitation of the performance of silica-core
fiber-based correlated photon pair sources) is highly reduced. With a
demonstrated coincident-to-accidental ratio equal to 63 and a pair generation
efficiency of about 10$^{-4}$ per pump pulse, this work opens the way for the
development of high quality correlated photon pair sources for quantum
communications.
