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arXiv · 2101.08280

Optimised Domain-engineered Crystals for Pure Telecom Photon Sources

Alexander Pickston·Francesco Graffitti·Peter Barrow·Christopher Morrison·Joseph Ho·Agata M. Brańczyk·Alessandro Fedrizzi
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Abstract

The ideal photon-pair source for building up multi-qubit states needs to produce indistinguishable photons with high efficiency. Indistinguishability is crucial for minimising errors in two-photon interference, central to building larger states, while high heralding rates will be needed to overcome unfavourable loss scaling. Domain engineering in parametric down-conversion sources negates the need for lossy spectral filtering allowing one to satisfy these conditions inherently within the source design. Here, we present a telecom-wavelength parametric down-conversion photon source that operates on the achievable limit of domain engineering. We generate photons from independent sources which achieve two-photon interference visibilities of up to $98.6\pm1.1\%$ without narrow-band filtering. As a consequence, we reach net heralding efficiencies of up to $67.5\%$, which corresponds to collection efficiencies exceeding $90\%$.

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Alexander Pickston, Francesco Graffitti, Peter Barrow, Christopher Morrison, Joseph Ho, Agata M. Brańczyk, Alessandro Fedrizzi. 2021-01-20. Optimised Domain-engineered Crystals for Pure Telecom Photon Sources. https://arxiv.org/abs/2101.08280

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