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Quantum information transfer using photons

Nature Photonics volume 8, pages 356–363 (2014)Cite this article

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Abstract

Optical communication channels have redefined the scope and applications of classical computing; similarly, photonic transfer of quantum information promises to open new horizons for quantum computing. The implementation of light–matter interfaces that preserve quantum information is technologically challenging, but key building blocks for such devices have recently been demonstrated by several research groups. Here, we outline the theoretical framework for information transfer between the nodes of a quantum network, review the current experimental state of the art and discuss the prospects for hybrid systems currently in development.

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Figure 1: A modified version of the deterministic atom–photon interface proposed by Cirac and co-workers8.
Figure 2: A heralded interface between two quantum memories does not rely on a direct optical connection between the memories.
Figure 3: One example of a light–matter interface.
Figure 4: A quantum process described by the matrix χ maps an arbitrary input density matrix ρin to the output matrix ρout.
Figure 5: Several platforms offer promising new approaches to quantum information transfer.

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Acknowledgements

We thank S. Olmschenk, C. Monroe, W. Rosenfeld, J. Majer, P. Bushev and H. de Riedmatten for providing images and feedback and G. Kirchmair, S. Ritter, B. Casabone, K. Friebe and Y. Colombe for helpful comments. We gratefully acknowledge support from the Austrian Science Fund (FWF) (Project Nos. F4002-N16, F4019-N16 and V252), the European Research Council through the Cryogenic Traps for Entanglement Research with IONs (CRYTERION) Project, the European Commission via the Atomic Quantum Technologies (AQUTE) Integrating Project, the Intelligence Advanced Research Projects Agency and the Institut für Quanteninformation GmbH.

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  1. Institut für Experimentalphysik, Universität Innsbruck, Technikerstraße 25, Innsbruck, 6020, Austria

    T. E. Northup & R. Blatt

  2. Institut für Quantenoptik und Quanteninformation der Österreichischen Akademie der Wissenschaften, Technikerstraße 21a, Innsbruck, 6020, Austria

    R. Blatt

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Northup, T., Blatt, R. Quantum information transfer using photons. Nature Photon 8, 356–363 (2014). https://doi.org/10.1038/nphoton.2014.53

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