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Non-Gaussian swapping of entangled resources

  • Fabio Dell’Anno
  • Daniela Buono
  • Gaetano Nocerino
  • Silvio De SienaEmail author
  • Fabrizio Illuminati
Article

Abstract

We investigate the continuous-variable entanglement swapping protocol in a non-Gaussian setting, with non-Gaussian states employed either as entangled inputs and/or as swapping resources. The quality of the swapping protocol is assessed in terms of the teleportation fidelity achievable when using the swapped states as shared entangled resources in a teleportation protocol. We thus introduce a two-step cascaded quantum communication scheme that includes a swapping protocol followed by a teleportation protocol. The swapping protocol is fed by a general class of tunable non-Gaussian states, the Squeezed Bell states, which, by means of controllable free parameters, allows to pass in a continuous way from Gaussian twin beams up to maximally non-Gaussian squeezed number states. In the realistic instance, taking into account the effects of losses and imperfections, we show that as the input two-mode squeezing increases, optimized non-Gaussian swapping resources allow for a monotonically increasing enhancement of the fidelity compared to the corresponding Gaussian setting. This result suggests that the use of non-Gaussian resources can be useful to guarantee the success of continuous-variable entanglement swapping in the presence of decoherence.

Keywords

Entanglement Swapping Non-Gaussianity 

Notes

Acknowledgements

We acknowledge the EU FP7 Cooperation STREP Project EQuaM—Emulators of Quantum Frustrated Magnetism, Grant Agreement No. 323714. We also acknowledge financial support from the Italian Minister of Scientific Research (MIUR) under the national PRIN program.

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Authors and Affiliations

  1. 1.Gruppo collegato di SalernoINFN Sezione di NapoliNapoliItaly
  2. 2.Liceo Statale V. De CaprariisAtripaldaItaly
  3. 3.Dipartimento di Ingegneria IndustrialeUniversità degli Studi di SalernoFiscianoItaly
  4. 4.Trenitalia spa, DPR Campania, Ufficio di Ingegneria della ManutenzioneIMC Campi FlegreiNaplesItaly
  5. 5.Rome Unit, Istituto di NanotecnologiaConsiglio Nazionale delle RicercheRomeItaly

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