Anticorrelation effect in femtosecond-pulse pumped type-II spontaneous parametric down-conversion - art. no. 011801

We report an experimental demonstration of an anticorrelation effect in fem tosecond-pulse pumped type-II spontaneous parametric down-conversion. Our e xperimental data, which is different from that of Atature et al. [Phys. Rev . Lett. 83, 1323 (2000)], confirmed the shallow symmetric "dip" that is pre dicted theoretically by Keller and Rubin [Phys. Rev. A 56, 1534 (1997)] and Grice and Walmsley [Phys. Rev. A 56, 1627 (1997)]. We show in this paper t hat the asymmetric dip observed in the literature is an artifact, which is caused by the asymmetric optical elements introduced into the beam path aft er the down-conversion process. The "partial distinguishability" theory sug gested by Atature et al. is therefore incorrect.