  Four-wave mixing (FWM) in optical fibre is a leading technique for generating
high-quality photon pairs. We report the generation of photon pairs by
spontaneous FWM in photonic crystal fibre pumped by a 1.5 GHz repetition-rate
vertical-external-cavity surface-emitting laser (VECSEL). The photon pairs
exhibit high count rates and a coincidence-to-accidental ratio of over 80. The
VECSEL's high repetition-rate, high average power, tunability, and small
footprint make this an attractive source for quantum key distribution and
photonic quantum-state engineering.
