Bound States in the Continuum in Asymmetric Dielectric Metasurfaces

Laser & Photonics Review, Journal Year: 2022, Volume and Issue: 17(3)

Published: Dec. 27, 2022

Abstract It is well established that for symmetry‐protected bound states in the continuum (BICs), introducing broken geometry symmetry a dielectric metasurface transforms such BIC into quasi‐BIC (QBIC) with high‐quality factor (Q‐factor). Typically, smaller asymmetry parameter, larger Q‐factor. However, it very challenging to fabricate nanostructures an ultra‐small thus limiting measured Q‐factor of QBIC. In this work, authors demonstrated BICs can be sustained at Γ‐point asymmetric metasurface, whose unit cell composed cuboid off‐centre hole inside it. Multipole decompositions and near‐field distributions indicate toroidal dipole dominates nature Furthermore, found robust against shape hole. Besides, two different wavelengths achieved by applying either rectangular or lattice. Finally, presented experimental verifications types fabricating silicon metasurfaces. Measurement results show QBIC reach almost 5,000. The may enrich library find exciting applications developing high‐performance photonics devices, as nanolasers, biosensors enhanced nonlinear harmonic generation.

Language: Английский

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Ultra-wideband terahertz fingerprint enhancement sensing and inversion model supported by single-pixel reconfigurable graphene metasurface

PhotoniX, Journal Year: 2024, Volume and Issue: 5(1)

Published: April 15, 2024

Abstract The molecular fingerprint sensing technology based on metasurface has unique attraction in the biomedical field. However, terahertz (THz) band, existing designs multi-pixel or angle multiplexing usually require more analyte amount possess a narrower tuning bandwidth. Here, we propose novel single-pixel graphene metasurface. Based synchronous voltage tuning, this enables ultra-wideband ( $$\sim$$ ∼ 1.5 THz) enhancement of trace analytes, including chiral optical isomers, with limit detection (LoD) ≤ 0.64 μg/mm 2 . signal 17.4 dB) originates from electromagnetically induced transparency (EIT) effect excited by metasurface, and ideal overlap between light field constrained single-layer (SLG) ultra-thin analyte. Meanwhile, due to nonlinear mechanism absorption envelope distortion is inevitable. To solve problem, universal spectrum inversion model developed for first time, restoration standard fingerprints reaches R max ≥ 0.99. In addition, asynchronous provides an opportunity realizing dynamic reconfiguration EIT resonance slow modulation broadband range. This work builds bridge THz potential applications active spatial modulators, devices imaging equipments.

Language: Английский

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The rise of electrically tunable metasurfaces

Science Advances, Journal Year: 2024, Volume and Issue: 10(34)

Published: Aug. 23, 2024

Metasurfaces, which offer a diverse range of functionalities in remarkably compact size, have captured the interest both scientific and industrial sectors. However, their inherent static nature limits adaptability for further applications. Reconfigurable metasurfaces emerged as solution to this challenge, expanding potential Among series tunable devices, electrically controllable devices garnered particular attention owing seamless integration with existing electronic equipment. This review presents recent progress reported respect providing an overview technological development trajectory current state art. In particular, we analyze major tuning strategies discuss applications spatial light modulators, optical waveguides, adaptable emissivity regulators. Furthermore, challenges opportunities associated implementation are explored, thereby highlighting bridge gap between electronics photonics enable groundbreaking systems.

Language: Английский

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Mie-Resonant Metaphotonics

Advances in Optics and Photonics, Journal Year: 2024, Volume and Issue: 16(3), P. 539 - 539

Published: June 4, 2024

Mie-resonant metaphotonics is a rapidly developing field that employs the physics of Mie resonances to control light at nanoscale. are excited in high-refractive-index transparent nanoparticles and voids created dielectric media, they can be used achieve wide range optical effects, including enhanced light–matter interaction, nonlinear topological photonics. Here, we review recent advances metaphotonics, with focus on their applications metasurfaces. Through comprehensive multipolar analysis, demonstrate complex interplay electric magnetic multipoles govern interaction light. Recent have unveiled diverse spectrum scattering phenomena achieved within precisely engineered structures. Within this framework, underlying mechanics first second Kerker conditions describe intricate mechanisms guiding these nanostructures’ light-scattering properties. Moreover, cover intriguing such as anapole bound or quasi-bound states continuum. Of profound interest numerous practical result from revelations. Ultrafast processes, emergence nanolasers, advancements magneto-optic devices represent just fraction transformative applications.

Language: Английский

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Electrically tunable optical metasurfaces

Photonics Insights, Journal Year: 2024, Volume and Issue: 3(3), P. R07 - R07

Published: Jan. 1, 2024

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Lithium Niobate Meta-Optics

ACS Photonics, Journal Year: 2022, Volume and Issue: 9(12), P. 3745 - 3763

Published: Nov. 9, 2022

The rapid development of optical metasurfaces, 2D ensembles engineered nanostructures, is presently underpinning a steady drive toward the miniaturization many functionalities and devices. list material platforms for metasurfaces rapidly expanding as, over past few years, we have witnessed surge in establishing meta-optical elements from high-index, highly transparent materials with strong nonlinear electro-optic properties. In particular, crystalline lithium niobate (LiNbO3), already prime integrated photonics, has shown great promise novel components, thanks to its large electro-optical coefficient second-order response broad transparency window ranging visible mid-infrared. Recent advances nanofabrication technology indeed marked new milestone LiNbO3 platforms, hence enabling first demonstrations LiNbO3-based metasurfaces. These seminal works set steppingstone realization ultrathin monolithic light sources, efficient quantum sources correlated photon pairs, as well modulators. Here, review these recent by providing perspective on their potential applications examining possible setbacks limitations emerging technologies.

Language: Английский

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Recent advances in strongly resonant and gradient all-dielectric metasurfaces

Materials Advances, Journal Year: 2022, Volume and Issue: 4(1), P. 11 - 34

Published: Nov. 11, 2022

We provide a critical overview of recent advances in all-dielectric, strongly resonant and gradient metasurfaces, as their performance is pushed to the extreme view emerging flat-optics applications.

Language: Английский

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Toward a universal metasurface for optical imaging, communication, and computation

Nanophotonics, Journal Year: 2022, Volume and Issue: 11(17), P. 3745 - 3768

Published: July 21, 2022

In recent years, active metasurfaces have emerged as a reconfigurable nanophotonic platform for the manipulation of light. Here, application an external stimulus to resonant subwavelength scatterers enables dynamic control over wavefront reflected or transmitted principle, are capable controlling key characteristic properties electromagnetic wave, such its amplitude, phase, polarization, spectrum, and momentum. A 'universal' metasurface should be able provide independent continuous all light deterministic shaping. this article, we discuss strategies realization goal. Specifically, describe approaches high performance metasurfaces, examine pathways achieving two-dimensional architectures, operating configurations optical imaging, communication, computation applications based on universal metasurface.

Language: Английский

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Electrically programmable solid-state metasurfaces via flash localised heating

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

Published: Feb. 22, 2023

In the last decades, metasurfaces have attracted much attention because of their extraordinary light-scattering properties. However, inherently static geometry is an obstacle to many applications where dynamic tunability in optical behaviour required. Currently, there a quest enable tuning metasurface properties, particularly with fast rate, large modulation by small electrical signals, solid state and programmable across multiple pixels. Here, we demonstrate electrically tunable driven thermo-optic effect flash-heating silicon. We show 9-fold change transmission <5 V biasing voltage rise-time <625 µs. Our device consists silicon hole array encapsulated transparent conducting oxide as localised heater. It allows for video frame rate switching over pixels that can be programmed. Some advantages proposed method compared other methods are possibility apply it visible near-infrared region, depth, working at regime, exhibiting low loss, input requirement, operating higher than video-rate speed. The furthermore compatible modern electronic display technologies could ideal personal devices such flat displays, virtual reality holography light detection ranging, fast, solid-state switches

Language: Английский

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Sub‐1‐Volt Electrically Programmable Optical Modulator Based on Active Tamm Plasmon

Advanced Materials, Journal Year: 2024, Volume and Issue: 36(15)

Published: Jan. 4, 2024

Abstract Reconfigurable optical devices hold great promise for advancing high‐density interconnects, photonic switching, and memory applications. While many modulators based on active materials have been demonstrated, it is challenging to achieve a high modulation depth with low operation voltage in the near‐infrared (NIR) range, which highly sought‐after wavelength window free‐space communication imaging Here, electrically switchable Tamm plasmon coupled poly(3,4‐ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) introduced. The device allows across entire NIR range by fully absorbing incident light even under epsilon near zero conditions. Optical exceeding 88% achieved using CMOS‐compatible of ±1 V. This facilitated precise electrical control charge carrier density through an electrochemical doping/dedoping process. Additionally, potential applications are extended non‐volatile multi‐memory state device, capable rewritable storage exhibiting long‐term potentiation/depression properties neuromorphic behavior.

Language: Английский

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