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arXiv · 1805.06577

Tunable entanglement distillation of spatially correlated down-converted photons

E. S. Gómez·P. Riquelme·M. A. Solis-Prosser·P. González·E. Ortega·G. B. Xavier·G. Lima
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Abstract

We report on a new technique for entanglement distillation of the bipartite continuous variable state of spatially correlated photons generated in the spontaneous parametric down-conversion process (SPDC), where tunable non-Gaussian operations are implemented and the post-processed entanglement is certified in real-time using a single-photon sensitive electron multiplying CCD (EMCCD) camera. The local operations are performed using non-Gaussian filters modulated into a programmable spatial light modulator and, by using the EMCCD camera for actively recording the probability distributions of the twin-photons, one has fine control of the Schmidt number of the distilled state. We show that even simple non-Gaussian filters can be finely tuned to a ~67% net gain of the initial entanglement generated in the SPDC process.

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E. S. Gómez, P. Riquelme, M. A. Solis-Prosser, P. González, E. Ortega, G. B. Xavier, G. Lima. 2018-05-17. Tunable entanglement distillation of spatially correlated down-converted photons. https://doi.org/10.1364/oe.26.013961

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