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Nonlocal flat optics

Nature Photonics volume 17, pages 36–47 (2023)Cite this article

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Abstract

In electromagnetics and photonics, ‘nonlocality’ refers to the phenomenon by which the response/output of a material or system at a certain point in space depends on the input field across an extended region of space. Although nonlocal effects and the associated wavevector/momentum dependence have often been neglected or seen as a nuisance in the context of metasurfaces, the emerging field of nonlocal flat optics seeks to exploit strong effective nonlocality to enrich and enhance their response. Here we summarize the latest advances in this field, focusing on its fundamental principles and various applications, from optical computing to space compression. The convergence of local and nonlocal flat optics may open exciting opportunities in the quest to control light, in real and momentum space, using ultra-thin platforms.

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Fig. 1: Local versus nonlocal flat optics.
Fig. 2: Photonic platforms to realize strong artificial nonlocality.
Fig. 3: Applications and opportunities enabled by nonlocal flat optics.
Fig. 4: Space compression with nonlocal spaceplates.

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Acknowledgements

We acknowledge support from the Air Force Office of Scientific Research (grant no. FA9550-22-1-0204) through A. Nachman.

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  1. School of Electrical and Computer Engineering, Cornell University, Ithaca, NY, USA

    Kunal Shastri & Francesco Monticone

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  1. Kunal Shastri
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Correspondence to Francesco Monticone.

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Shastri, K., Monticone, F. Nonlocal flat optics. Nat. Photon. 17, 36–47 (2023). https://doi.org/10.1038/s41566-022-01098-5

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