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Quantum nonlinear optics — photon by photon

Abstract

The realization of strong interactions between individual photons is a long-standing goal of both fundamental and technological significance. Scientists have known for over half a century that light fields can interact inside nonlinear optical media, but the nonlinearity of conventional materials is negligible at the light powers associated with individual photons. Nevertheless, remarkable advances in quantum optics have recently culminated in the demonstration of several methods for generating optical nonlinearities at the level of individual photons. Systems exhibiting strong photon–photon interactions enable a number of unique applications, including quantum-by-quantum control of light fields, single-photon switches and transistors, all-optical deterministic quantum logic, and the realization of strongly correlated states of light and matter.

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Figure 1: Quantum nonlinear optics in a cavity.
Figure 2: Quantum networks.
Figure 3: Nonlinear optics using electromagnetically induced transparency (EIT).
Figure 4: Rydberg-blockade-mediated interaction between slowly propagating photons.
Figure 5: Many-body quantum dynamics in a nonlinear medium.
Figure 6: Quantum interfaces between atoms and nanophotonic systems.

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Acknowledgements

The authors acknowledge C. Adams, I. Cirac, W. Chen, Y. Chu, E. Demler, M. Fleischhauer, O. Firstenberg, S. Harris, V. Gritsev, A. Gorshkov, A. Imamoğlu, H. J. Kimble, N. de Leon, M. Loncar, H. Tanji-Suzuki, T. Peyronel, T. Pohl, G. Rempe, A. Sørensen, M. O. Scully, T. Tiecke, J. Thompson, J. Vuckovic, S. Yelin, A. Zibrov, and P. Zoller for the many discussions and contributions that resulted in the work described in this Review. Support from the National Science Foundation, Harvard-MIT Center for Ultracold Atoms, Defense Advanced Research Projects Agency, Air Force Office of Scientific Research Multidisciplinary University Research Initiative, Packard Foundation, and European project Graphene-Based Single-Photon Nonlinear Optical Devices (GRASP) is gratefully acknowledged. D.E.C. acknowledges support from Fundacio Privada Cellex Barcelona and the Ramon y Cajal programme.

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Chang, D., Vuletić, V. & Lukin, M. Quantum nonlinear optics — photon by photon. Nature Photon 8, 685–694 (2014). https://doi.org/10.1038/nphoton.2014.192

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