Spontaneous spectral phase conjugation for coincident frequency entanglement

Spontaneous parametric processes pumped transversely with short pulses are studied under a unified framework, which proves that such processes can efficiently generate entangled photon pairs with time anticorrelation and frequency correlation. Improvements upon previously proposed schemes can be made by the use of quasi-phase-matching, four-wave mixing, and cross-phase-modulation compensation. The use of frequency-correlated photons in the Hung-Ou-Mandel interferometer is studied.