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  • Review Article
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Near-zero refractive index photonics

Nature Photonics volume 11, pages 149–158 (2017)Cite this article

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An Erratum to this article was published on 04 April 2017

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Abstract

Structures with near-zero parameters (for example, media with near-zero relative permittivity and/or relative permeability, and thus a near-zero refractive index) exhibit a number of unique features, such as the decoupling of spatial and temporal field variations, which enable the exploration of qualitatively different wave dynamics. This Review summarizes the underlying principles and salient features, physical realizations and technological potential of these structures. In doing so, we revisit their distinctive impact on multiple optical processes, including scattering, guiding, trapping and emission of light. Their role in emphasizing secondary responses of matter such as nonlinear, non-reciprocal and non-local effects is also discussed.

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Figure 1: Tunnelling through distorted channels.
Figure 2: Highly directive emission and geometry-invariant phenomena.
Figure 3: Nonlinear phenomena in structures with near-zero parameters.
Figure 4: Different realizations of structures with near-zero parameters.

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Change history

  • 06 March 2017

    Owing to technical problems, this Review Article was published online later than the date given in the print version. The published date should read '1 March 2017', and is correct in the online versions.

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Acknowledgements

This work is supported in part by the US Air Force Office of Scientific Research (AFOSR) Multidisciplinary University Research Initiative (MURI) award no. FA9550-12-1-0488 and in part by the AFOSR MURI award no. FA9550-14-1-0389. The authors would also like to acknowledge partial support from the Vannevar Bush Faculty Fellowship programme sponsored by the Basic Research Office of the Assistant Secretary of Defense for Research and Engineering and funded by the Office of Naval Research through grant N00014-16-1-2029.

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  1. Department of Electrical and Systems Engineering, University of Pennsylvania, Philadelphia, 19104, Pennsylvania, USA

    Iñigo Liberal & Nader Engheta

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  1. Iñigo Liberal
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  2. Nader Engheta
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Correspondence to Nader Engheta.

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Liberal, I., Engheta, N. Near-zero refractive index photonics. Nature Photon 11, 149–158 (2017). https://doi.org/10.1038/nphoton.2017.13

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