Tunable metasurfaces towards versatile metalenses and metaholograms: a review

Advanced Photonics, Journal Year: 2022, Volume and Issue: 4(02)

Published: March 7, 2022

Metasurfaces have attracted great attention due to their ability manipulate the phase, amplitude, and polarization of light in a compact form. Tunable metasurfaces been investigated recently through integration with mechanically moving components electrically tunable elements. Two interesting applications, particular, are vary focal point metalenses switch between holographic images. We present recent progress on focused metaholograms, including basic working principles, advantages, disadvantages each mechanism. classify stimuli based source electrical bias, as well others such thermal mechanical modulation. conclude by summarizing providing our perspectives for further development metasurfaces.

Language: Английский

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Pushing the Limits of Functionality‐Multiplexing Capability in Metasurface Design Based on Statistical Machine Learning

Advanced Materials, Journal Year: 2022, Volume and Issue: 34(16)

Published: Feb. 15, 2022

As 2D metamaterials, metasurfaces provide an unprecedented means to manipulate light with the ability multiplex different functionalities in a single planar device. Currently, most pursuits of multifunctional resort empirically accommodating more at cost increasing structural complexity, little effort investigate intrinsic restrictions given meta-atoms and thus ultimate limits design. In this work, it is proposed embed machine-learning models both gradient-based nongradient optimization loops for automatic implementation metasurfaces. Fundamentally from traditional two-step approach that separates phase retrieval meta-atom design, end-to-end framework facilitates full exploitation prescribed design space pushes capacity its physical limit. With single-layer structure can be readily fabricated, metasurface focusing lenses holograms are experimentally demonstrated near-infrared region. They show up eight controllable responses subjected combinations working frequencies linear polarization states, which unachievable by conventional physics-guided approaches. These results manifest superior capability data-driven scheme photonic will accelerate development complex devices systems optical display, communication, computing.

Language: Английский

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Photonic Encryption Platform via Dual-Band Vectorial Metaholograms in the Ultraviolet and Visible

ACS Nano, Journal Year: 2022, Volume and Issue: 16(3), P. 3546 - 3553

Published: Feb. 19, 2022

Metasurface-driven optical encryption devices have attracted much attention. Here, we propose a dual-band vectorial metahologram in the visible and ultraviolet (UV) regimes for encryption. Nine polarization-encoded holograms are observed under UV laser illumination, while another independent hologram appears illumination. The proposed engineered silicon nitride, which is transparent UV, employed to demonstrate hologram. holographic images different polarization states encoded using pixelated metasurface. experimentally implemented by stacking individual metasurfaces that operate visible. can be decrypted provide first key, state, used decode password hidden through use of an analyzer. Considering property invisible naked eye, multiple channels hologram, decoupling, demonstrated device could applied various high-security anticounterfeiting applications.

Language: Английский

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Artificial Intelligence in Meta-optics

Chemical Reviews, Journal Year: 2022, Volume and Issue: 122(19), P. 15356 - 15413

Published: June 24, 2022

Recent years have witnessed promising artificial intelligence (AI) applications in many disciplines, including optics, engineering, medicine, economics, and education. In particular, the synergy of AI meta-optics has greatly benefited both fields. Meta-optics are advanced flat optics with novel functions light-manipulation abilities. The optical properties can be engineered a unique design to meet various demands. This review offers comprehensive coverage synergy. After providing an overview meta-optics, we categorize discuss recent developments integrated by these two topics, namely for AI. former describes how apply research design, simulation, information analysis, application. latter reports development Al system computation via meta-optics. will also provide in-depth discussion challenges this interdisciplinary field indicate future directions. We expect that inspire researchers fields benefit next generation intelligent device design.

Language: Английский

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Liquid crystal-powered Mie resonators for electrically tunable photorealistic color gradients and dark blacks

Light Science & Applications, Journal Year: 2022, Volume and Issue: 11(1)

Published: April 29, 2022

Taking inspiration from beautiful colors in nature, structural produced nanostructured metasurfaces have shown great promise as a platform for bright, highly saturated, and high-resolution colors. Both plasmonic dielectric materials been employed to produce static that fulfil the required criteria high-performance color printing, however, practical applications dynamic situations, form of tunability is desirable. Combinations additive palette red, green, blue enable expression further beyond three primary colors, while simultaneous intensity modulation allows access full gamut. Here, we demonstrate an electrically tunable metasurface can represent saturated pixels be dynamically continuously controlled between on off states using liquid crystals. We use this experimentally realize ultrahigh-resolution active multicolor cryptographic applications, toward full-color reflective displays.

Language: Английский

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Integrated metasurfaces for re-envisioning a near-future disruptive optical platform

Light Science & Applications, Journal Year: 2023, Volume and Issue: 12(1)

Published: June 20, 2023

Abstract Metasurfaces have been continuously garnering attention in both scientific and industrial fields, owing to their unprecedented wavefront manipulation capabilities using arranged subwavelength artificial structures. To date, research has mainly focused on the full control of electromagnetic characteristics, including polarization, phase, amplitude, even frequencies. Consequently, versatile possibilities wave achieved, yielding practical optical components such as metalenses, beam-steerers, metaholograms, sensors. Current is now integrating aforementioned metasurfaces with other standard (e.g., light-emitting diodes, charged-coupled devices, micro-electro-mechanical systems, liquid crystals, heaters, refractive elements, planar waveguides, fibers, etc.) for commercialization miniaturization trends devices. Herein, this review describes classifies metasurface-integrated components, subsequently discusses promising applications platforms those augmented/virtual reality, light detection ranging, In conclusion, presents several challenges prospects that are prevalent field order accelerate metasurfaces-integrated platforms.

Language: Английский

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Disordered-nanoparticle–based etalon for ultrafast humidity-responsive colorimetric sensors and anti-counterfeiting displays

Science Advances, Journal Year: 2022, Volume and Issue: 8(10)

Published: March 11, 2022

The development of real-time and sensitive humidity sensors is in great demand from smart home automation modern public health. We hereby proposed an ultrafast full-color colorimetric sensor that consists chitosan hydrogel sandwiched by a disordered metal nanoparticle layer reflecting substrate. This hydrogel-based resonator changes its resonant frequency to external conditions because the hydrogels are swollen under wet state contracted dry state. response time ~10 4 faster than conventional Fabry-Pérot design. origins fast gas permeation membrane pores created gaps between nanoparticles. Such instantaneous tunable new then exploited for sensors, anti-counterfeiting applications, high-resolution displays.

Language: Английский

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Optical metasurfaces for generating and manipulating optical vortex beams

Nanophotonics, Journal Year: 2022, Volume and Issue: 11(5), P. 941 - 956

Published: Jan. 7, 2022

Optical vortices (OVs) carrying orbital angular momentum (OAM) have attracted considerable interest in the field of optics and photonics owing to their peculiar optical features extra degree freedom for information. Although there been significant efforts realize OVs using conventional optics, it is limited by large volume, high cost, lack design flexibility. metasurfaces recently tremendous due unprecedented capability manipulation amplitude, phase, polarization, frequency light at a subwavelength scale. revolutionized concepts photonics, providing new platform develop ultrathin devices realization resolution. In this article, we will review recent progress metasurface-based OVs. We provide comprehensive discussion on OVs, including OAM superposition, sorting, multiplexing, holography, nonlinear generation manipulation. The rapid development metasurface play an important role many relevant research fields. expect that fuel continuous wearable portable consumer electronics where low-cost miniaturized related systems are demand.

Language: Английский

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Schrödinger’s red pixel by quasi-bound-states-in-the-continuum

Science Advances, Journal Year: 2022, Volume and Issue: 8(8)

Published: Feb. 23, 2022

While structural colors are ubiquitous in nature, saturated reds mysteriously absent. This long-standing problem of achieving Schrödinger's red demands sharp transitions from "stopband" to a high-reflectance "passband" with total suppression higher-order resonances at blue/green wavelengths. Current approaches based on nanoantennas insufficient satisfy all conditions simultaneously. Here, we designed Si support two partially overlapping quasi-bound-states-in-the-continuum modes gradient descent algorithm achieve spectral edges Meanwhile, high-order wavelengths suppressed via engineering the substrate-induced diffraction channels and absorption amorphous Si. design produces possibly most brightest ~80% reflectance, exceeding vertex sRGB even cadmium pigment. Its nature being sensitive polarization illumination angle could be potentially used for information encryption, this proposed paradigm generalized other color pixels.

Language: Английский

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Multimodal-Responsive Circularly Polarized Luminescence Security Materials

Journal of the American Chemical Society, Journal Year: 2023, Volume and Issue: 145(7), P. 4246 - 4253

Published: Feb. 1, 2023

Nations, industries, and aspects of everyday life have undergone forgery counterfeiting ever since the emergence commercialization. Securing documents products with anticounterfeit additives shows promise for authentication, allowing one to combat ever-increasing global counterfeiting. One most-used effective encryption strategy is combine optical-security markers on required protection objects; however, state-of-the-art labels still suffer from imitation due their poor complexity easy forecasting, as a result deterministic production. Developing advanced anticounterfeiting tags unusual optical characters further incorporating complex security features are desired achieve multimodal, unbreakable authentication capacity; unfortunately, this has not yet been achieved. Here, we prepare series stable circularly polarized luminescence (CPL) materials, composed toxicity-free, high-quality-emitting inorganic quantum dots (QDs) liquid crystals, using designed helical-coassembly strategy. This CPL system achieves figure merit (FM, assessing performance both dissymmetry yield) value 0.39, fulfilling practical demands applications. Based these structures, produce type multimodal-responsive materials (MRSMs) that exhibits six different stimuli-responsive modes, including light activation, polarization, temperature, voltage, pressure, view angle. Thus, show proof-of-principle blockchain-like integrated system, multimodal-responsive, interactive/changeable information encryption–decryption. We encapsulate obtained into fiber expand our work flexible fabrics, is, building an intelligent textile color-adaptable function along environmental change.

Language: Английский

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