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arXiv · 1605.03777

On-chip generation of heralded photon-number states

Panagiotis Vergyris·Thomas Meany·Tommaso Lunghi·James Downes·M. J. Steel·Michael J. Withford·Olivier Alibart·Sébastien Tanzilli
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Abstract

Beyond the use of genuine monolithic integrated optical platforms, we report here a hybrid strategy enabling on-chip generation of configurable heralded two-photon states. More specifically, we combine two different fabrication techniques, \textit{i.e.}, non-linear waveguides on lithium niobate for efficient photon-pair generation and femtosecond-laser-direct-written waveguides on glass for photon manipulation. Through real-time device manipulation capabilities, a variety of path-coded heralded two-photon states can be produced, ranging from product to entangled states. Those states are engineered with high levels of purity, assessed by fidelities of 99.5$\pm$8\% and 95.0$\pm$8\%, respectively, obtained via quantum interferometric measurements. Our strategy therefore stands as a milestone for further exploiting entanglement-based protocols, relying on engineered quantum states, and enabled by scalable and compatible photonic circuits.

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Panagiotis Vergyris, Thomas Meany, Tommaso Lunghi, James Downes, M. J. Steel, Michael J. Withford, Olivier Alibart, Sébastien Tanzilli. 2016-05-12. On-chip generation of heralded photon-number states. https://doi.org/10.1038/srep35975

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