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arXiv · 1504.03776

On the effects of self- and cross-phase modulation on photon purity for four-wave mixing photon-pair sources

Bryn Bell·Alex McMillan·Will McCutcheon·John Rarity
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Abstract

We consider the effect of self-phase modulation and cross-phase modulation on the joint spectral amplitude of photon pairs generated by spontaneous four-wave mixing. In particular, the purity of a heralded photon from a pair is considered, in the context of schemes that aim to maximise the purity and minimise correlation in the joint spectral amplitude using birefringent phase-matching and short pump pulses. We find that non-linear phase modulation effects will be detrimental, and will limit the quantum interference visibility that can be achieved at a given generation rate. An approximate expression for the joint spectral amplitude with phase modulation is found by considering the group velocity walk-off between each photon and the pump, but neglecting the group-velocity dispersion at each wavelength. The group-velocity dispersion can also be included with a numerical calculation, and it is shown that it only has a small effect on the purity for the realistic parameters considered.

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Bryn Bell, Alex McMillan, Will McCutcheon, John Rarity. 2015-04-15. On the effects of self- and cross-phase modulation on photon purity for four-wave mixing photon-pair sources. https://doi.org/10.1103/physreva.92.053849

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