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From metamaterials to metadevices

Metamaterials are man-made structures that allow optical properties to be shaped on length scales far smaller than the wavelength of light. Although metamaterials were initially considered mainly for static applications, this Review summarizes efforts towards an active functionality that enables a much broader range of photonic device applications.

Abstract

Metamaterials, artificial electromagnetic media that are structured on the subwavelength scale, were initially suggested for the negative-index 'superlens'. Later metamaterials became a paradigm for engineering electromagnetic space and controlling propagation of waves: the field of transformation optics was born. The research agenda is now shifting towards achieving tunable, switchable, nonlinear and sensing functionalities. It is therefore timely to discuss the emerging field of metadevices where we define the devices as having unique and useful functionalities that are realized by structuring of functional matter on the subwavelength scale. In this Review we summarize research on photonic, terahertz and microwave electromagnetic metamaterials and metadevices with functionalities attained through the exploitation of phase-change media, semiconductors, graphene, carbon nanotubes and liquid crystals. The Review also encompasses microelectromechanical metadevices, metadevices engaging the nonlinear and quantum response of superconductors, electrostatic and optomechanical forces and nonlinear metadevices incorporating lumped nonlinear components.

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Figure 1: Reconfigurable metamaterials.
Figure 2: Electro-optical and liquid-crystal metadevices.
Figure 3: Phase-change and superconducting metadevices.
Figure 4: Ultrafast metadevices, varactor metamaterials and electromagnetic forces.

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Acknowledgements

We thank I. Yangs for discussions, and T. Roy and D. Powel for assistance with preparing the manuscript. We acknowledge the support of the Defence Science and Technology Laboratory (UK), Engineering and Physical Sciences Research Council (UK), Royal Society (London), Australian Research Council and collaboration support through the Centre for Ultrahigh-bandwidth Devices for Optical Systems (Australia), and Ministry of Education, Singapore, grant number MOE2011-T3-1-005.

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N.I.Z initiated the sections on reconfigurable, electro-optical, phase change, superconducting and ultrafast metadevices; Y.S.K initiated the sections on liquid crystal metadevices, nonlinear metadevices with varactors and metadevices driven by electromagnetic forces; both authors contributed equally to editing.

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Correspondence to Nikolay I. Zheludev.

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Zheludev, N., Kivshar, Y. From metamaterials to metadevices. Nature Mater 11, 917–924 (2012). https://doi.org/10.1038/nmat3431

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