We design an ultra-thin terahertz metamaterial absorber based on graphene/MgF(2) multilayer stacking unit cells arrayed Au film plane and theoretically demonstrate a dual-band total absorption effect. Due to strong anisotropic permittivity, the possess hyperbolic dispersion. The electric magnetic dipole resonances between make impedance of match that free space, which induces two peaks in range. These are insensitive polarization nearly omnidirectional for incident angle. But intensity...

Abstract Chiral metasurface based on bound state in the continuum (BIC) possesses extremely high Q factor. However, intrinsic chiral BIC only can be realized by breaking out‐of‐plane mirror symmetry with complicated 3D structures. In this work, a design of planar supporting orthogonal BICs is proposed. The coupling strength, eigenfrequency, and radiation loss two quasi‐BICs tuned parameters. By adjusting parameters, merge to an exceptional point (EP). Around EP, one transforms circular...

Smith-Purcell radiation results from charged particles that move closely to a periodic structure. In this work, we report the on-demand control of by rationally designed graphene metasurfaces. Not only can strongly enhance efficiency radiation, but also amplitude, phase, and polarization state radiated wave be fully manipulated tuning structure Fermi level metasurface. Through designing geometric parameters each unit cell metasurface, intensity changed zero maximum. Meanwhile, phase at any...

As an artificial planar composite medium, optical metasurfaces exhibit powerful multidimensional modulations at the subwavelength scale. With aid of intelligent algorithms, versatile wavefront engineering and holographic multiplexing based on are being intensively developed. Micronano manufacturing technology provides indispensable support for proof-of-concept mass production. these advanced technologies, have been developed a wide range applications their compactness, versatility,...

Abstract Tunable mode converter is a key component of channel switching and routing for optical communication system by adopting mode-division multiplexing. Traditional hardly implements high-order conversion dynamic tunability simultaneously. In this study, we design tunable filled with liquid crystal, which can convert fundamental into multiple modes (TE 0 , TE 1 2 ) good performance low intrinsic loss. For multiple-objective task, propose an inverse framework based on the adjoint method....

Abstract A moving charged particle, such as an electron, can radiate light due to the interaction between its Coulomb field and surrounding matter. This phenomenon has spawned great interest in fields of physics, electron microscopy, optics, biology, materials science. Since radiation generated by particles strongly depends on matter, artificially engineered with exotic electromagnetic optic properties, including metamaterials metasurfaces, provide unprecedented opportunity tailor particle...

We design a tunable terahertz metasurface, which consists of two different trapezoid graphene ribbons patterned in opposite directions on gold film, separated by thin dielectric spacer. The kinds can cover nearly 2π phase shift with high reflection efficiency spectral regions so that the metasurface reflect frequency waves to totally directions. By changing Fermi level ribbons, response proposed be adjusted, and as result, spectrum splitting realized. present provides powerful way control...

By controlling light fields in subwavelength scales, metasurfaces enable novel ways for miniaturization and integration of spectral imaging system. Metasurfaces supporting quasi bound states the continuum (quasi-BICs) can control quality factor response by changing structural parameters. In this work, we present an ultra-compact multispectral device, whereby modulation is achieved meta-atoms arrays quasi-BICs. The designed meta-atom array serve as filters over a wide range wavelengths, which...

Monolayer transition metals dichalcogenides (TMDs) have been coupled to bound-state in the continuum (BIC) hosted dielectric structures attain high second harmonic generation (SHG). However, transvers electric modes are strongly localized waveguides result fairly weak exciton-photon coupling monolayer TMD placed on surface. To achieve SHG few-layers TMDs based BIC-inspired structure is a challenge. Here, we report BIC metasurface with quality factor (Q-factor), tunability, and...

Abstract The quasi-bound state in the continuum (quasi-BIC) of dielectric metasurface provides a crucial platform for sensing, because its almost infinite Q -factor can greatly enhance interactions between light waves and analytes. In this work, we proposed an ultrasensitive all-dielectric sensor composed periodic rectangular amorphous silicon pillars on quartz substrate. By breaking symmetry two unit cell, high quasi-BIC continuous near-infrared band be excited. magnetic toroidal dipole...

Abstract We design a soft infrared metamaterial absorber based on gold nanorods dispersed in liquid crystal (LC) placed film and theoretically investigate its total absorption character. Because the align with LC molecule, nanorods/LC hybrid exhibits different permittivity as function of tilt angle LC. At certain angle, shows an omnidirectional effect. By changing by external electric field, character can be adjusted. The also depends concentration, geometric dimension defect nanorod...

Abstract The enhancement of electromagnetic field with high Q factor in metasurfaces has attracted extensive attention researchers. Magneto-optical (MOMS) provide approaches controllable magnetic fields to modulate the optical response, which contributes towards magneto-optical Kerr effect nanophotonic devices. However, it is challenging for MOMS obtain narrow spectra peak factors. Here, we propose MOMS-supported quasi-bound states continuum (quasi-BIC) and theoretically investigate...

In this paper, we report all-optical manipulation of magnetization in ferromagnetic Co/Pt thin films enhanced by plasmonic resonances. By annealing a Au layer, fabricate large-area nanoislands on top the magnetic films, which show resonances around wavelength 606 nm. Using customized magneto-optical Kerr effect setup, experimentally observe an 18.5% decrease minimum laser power required to manipulate magnetization, comparing on- and off-resonance conditions. The results are very good...

Optical geometric-phase metasurfaces provide a robust and efficient means for light wave control by simply manipulating the spatial orientations of in-plane anisotropic meta-atoms, where polarization conversion plays vital role. However, concept acoustic modulation field remains unexplored because airborne waves lack similar optical process. In this work, new type meta-atom with deep-subwavelength feature size is theoretically investigated further applied to engineering based on emerged...

Metasurfaces are promising platforms for integrated compact optical systems. Traditional metasurface holography design algorithms limited to information capacity due finite spatial bandwidth production, which is insufficient the growing demand big data storage and encryption. Here, we propose demonstrate deep learning empowered ultra-dense complex-amplitude using step-moving cascaded metasurfaces. Using artificial intelligence optimization strategy, barriers of traditional can be conquered...

In this work, we utilize thin dielectric meta-atoms placed on a silver substrate to efficiently enhance and manipulate the third harmonic generation. We theoretically experimentally reveal that when structural symmetry of meta-atom is incompatible with lattice an array, some generalized nonlinear geometric phases appear, which offers new possibilities for generation control beyond accessible symmetries governed by selection rule. The underlying mechanism attributed modified rotation...

Abstract Metasurfaces based on geometric phase acquired from the conversion of optical spin states provide a robust control over wavefront light, and have been widely employed for construction various types functional metasurface devices. However, this powerful approach cannot be readily transferred to manipulation acoustic waves because do not possess degree freedom. Here, we propose concept geometric-phase meta-array by leveraging orbital angular momentum waves, where well-defined...

Resettlement is an important part of water conservancy and hydropower projects, its development a proper means comprehensively promoting rural revitalization. The issue sustainable livelihoods in resettlement has always attracted significant attention. Based on the traditional livelihood framework, this paper attempts to incorporate psychological capital construct index system for caused by projects. It also adopts research data from 138 migrant sites along middle route South North Water...

Abstract In this paper, we have designed a metasurface based on electrically tunable Mie-type resonators and theoretically demonstrated its response to electromagnetic waves with varying frequency. The consists of disk-like ferroelectric arrayed metal film the upper surface is covered by ion gel which transparent for incident wave. Using as electrodes, permittivity can be adjusted an external electric field and, result, reflection phase dynamically in relatively wide range. By programmable...

Metamaterials with tailored electromagnetic properties hold great promise for the manipulation of waves. Here, we propose an intriguing off-resonance meta-device to control polarization states and dispersive features waves simultaneously. The proposed is composed stacks bilayer gear-like metallic patterns, which exhibit significant anisotropy due geometric asymmetry. results show that considered operates in a transmission mode can achieve broadband nondispersive cross-polarization high...

Abstract Wave shaping plays an important role in on‐chip signal processing. However, previously reported photonics elements exhibit limited control capabilities or require complex nanofabrication techniques. Here, metadevice is proposed for multiport beam splitting based on a 1D slots array the silicon‐on‐insulator platform, which has advantages of high efficiency, full 2π phase shift, and easy design scheme. The experimentally demonstrated at 1550 nm, shows different numbers splits. This...