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With rapid development of holography, metasurface-based holographic communication scheme shows great potential in development of adaptive electromagnetic function. However, conventional passive metasurfaces are severely limited by poor reconfigurability, which makes it difficult to achieve wavefront manipulations in real time. Here, we propose a holographic communication strategy that on-demand target information is firstly acquired and encoded via a depth camera integrated with modified YOLOv5s target detection algorithm, then transmitted by software defined radio modules with long term evolution at 5 GHz, and finally reproduced in the form of holographic images by spin-decoupled programmable coding metasurfaces at 12 GHz after decoding through modified Gerchberg–Saxton algorithm. Experiments are conducted to demonstrate the brand-new concept of optical information conversion to electromagnetic one via above intelligent scheme. Our strategy may open a novel avenue toward applications of near-field communication based on adaptive variation of electric field patterns (i.e. holographic images).

Camouflage is an important technology in various scenarios. Usually, this involves the visible compatibility of the background, which however is facile under infrared thermal radiation detection. The simultaneous visible and thermal camouflage are challenging because it requires full and decoupled manipulations of visible reflection and infrared emissivity using one single device, let alone to its adaptivity to complex environments. Here, we report a programmable, colored thermal camouflage at 3–5 μm and 8–14 μm based on mode coupling in phase-change In3SbTe2 materials. A series of industry-friendly colored multilayer thermal emitters are designed consisting of an anti-reflectance layer for structure coloration above a coupled nanocavity for IR modulation, which easily realizes the complete decoupled control of visible color and infrared emissivity. Our solution features independent structural visible colors in the full visible range and continuously programmable dual-band emissivity modulation with up to 90 % absolute tuning range. Our work facilitates near optimal camouflage and anti-counterfeiting solution for visible-infrared multi-band compatibility of complex environments under different temperatures and colored appearances.

Abstract Lung adenocarcinoma (LUAD) remains one of the most aggressive tumors and the efficacy of conventional treatment has been bleak. Nowadays, gene-targeted therapy has become a new favorite in tumor therapy. Herein, we investigated the effect of platelet derived growth factor BB (PDGFBB) on LUAD. Firstly, PDGFBB was upregulated in LUAD patients and closely linked with poor survival. Furthermore, the expression of PDGFBB and PDGFRα/β in LUAD cells was higher than that in normal lung cells. By loss-of-function with herpes simplex virus (HSV)-PDGFi-shRNA, we found that PDGFBB knockdown caused a significant decrease in proliferation and migration, but evoked apoptosis of LUAD cells in vitro. Conversely, exogenous PDGFBB held adverse effect. Additionally, A549 cells with PDGFBB knockdown had a low probability of tumorigenesis in vivo. Moreover, PDGFBB knockdown restrained the growth of xenografts derived from normal A549 cells. Mechanistically, PDGFBB knockdown suppressed PI3K/AKT and Ras/MAPK signaling, while PDGFBB was the opposite. Therefore, we concluded that PDGFBB might facilitate the tumorigenesis and malignancy of LUAD through its functional downstream nodes—PI3K/AKT and Ras/MAPK signaling, which supported that PDGFBB could serve as a rational therapeutic target for LUAD.

Abstract Optical materials capable of dynamically manipulating electromagnetic waves are an emerging field in memories, optical modulators, and thermal management. Recently, their multispectral design preliminarily attracts much attention, aiming to enhance their efficiency and integration of functionalities. However, the multispectral manipulation based on these materials is challenging due to their ubiquitous wavelength dependence restricting their capacity to narrow wavelengths. In this article, we cascade multiple tunable optical cavities with selective-transparent layers, enabling a universal approach to overcoming wavelength dependence and establishing a multispectral platform with highly integrated functions. Based on it, we demonstrate the multispectral (ranging from 400 nm to 3 cm), fast response speed (0.9 s), and reversible manipulation based on a typical phase change material, vanadium dioxide. Our platform involves tandem VO2-based Fabry–Pérot (F-P) cavities enabling the customization of optical responses at target bands independently. It can achieve broadband color-changing capacity in the visible region (a shift of ~60 nm in resonant wavelength) and is capable of freely switching between three typical optical models (transmittance, reflectance, and absorptance) in the infrared to microwave regions with drastic amplitude tunability exceeding 0.7. This work represents a state-of-art advance in multispectral optics and material science, providing a critical approach for expanding the multispectral manipulation ability of optical systems.

Achieving high-efficient and low-power communication is pivotal yet very challenging in the emerging technologies. Unlike conventional backscatter communication system, we propose and demonstrate an amplitude-reconfigurable metasurface loaded with PIN diodes to build a front-back scattering communication transmitter, which features the exclusive advantages of full-space secondary modulation of the ambient signals with high energy utilization efficiency. Meanwhile, this device can eliminate the interference originated from the ambient source by polarization conversion in the transmission channel. At a modulation rate of 800 kbps and a distance of 80 m, our system can achieve distortion-free transmission of a picture with size of 200 × 200 pixels. In addition, multiple amplitude-shift-keying modulation is also realized by segmenting the metasurface to further increase the communication rate. Due to the advantages of high spectral efficiency and low energy consumption, this system can be widely used in future engineering applications for the internet of things, especially for smart home, agriculture environmental monitoring, wearable sensing and others.

Abstract As a two-dimensional planar material with low depth profile, a metasurface can generate non-classical phase distributions for the transmitted and reflected electromagnetic waves at its interface. Thus, it offers more flexibility to control the wave front. A traditional metasurface design process mainly adopts the forward prediction algorithm, such as Finite Difference Time Domain, combined with manual parameter optimization. However, such methods are time-consuming, and it is difficult to keep the practical meta-atom spectrum being consistent with the ideal one. In addition, since the periodic boundary condition is used in the meta-atom design process, while the aperiodic condition is used in the array simulation, the coupling between neighboring meta-atoms leads to inevitable inaccuracy. In this review, representative intelligent methods for metasurface design are introduced and discussed, including machine learning, physics-information neural network, and topology optimization method. We elaborate on the principle of each approach, analyze their advantages and limitations, and discuss their potential applications. We also summarize recent advances in enabled metasurfaces for quantum optics applications. In short, this paper highlights a promising direction for intelligent metasurface designs and applications for future quantum optics research and serves as an up-to-date reference for researchers in the metasurface and metamaterial fields.

Achieving multifunctional wavefront manipulations of waves with a flat and thin plate is pivotal for high-capacity communications, which however is also challenging. A multi-layer metasurface with suppressed mode crosstalk provides an efficient recipe primarily for circular polarization, but all multiple functionalities still are confined to locked spin states and modes. Here, a multifunctional metasurface with spin-decoupled full-space wavefront control is reported by multiplexing both linear momentum and frequency degree of freedom. We employed vertically cascaded quadrangular patches and crossbars to integrate both geometric and dynamic phases and realized four channels between two spin states and two frequencies in distinct scattering modes (transmission and reflection). For verification, a proof-of-concept metadevice with four-port wavefront manipulations is experimentally demonstrated, exhibiting distinct functionalities including spin- and frequency-dependent focusing, quad-beam radiation, anomalous reflections, and Bessel beam generation. Our finding of full-space spin-decoupled metasurfaces would be important for high-capacity communications, multifunctional radar detections, and other applications.

The rapid development of metamaterials offers a new avenue to achieve exotic electromagnetic properties, such as perfect absorption for important stealth engineering applications. So far, there are few demonstrations of wide-angle broadband absorption, due to the stringent impedance matching requirement. Here, inspired by the concept of log-periodic dipole antenna (LPDA) for broadband emission, we propose a wide-angle broadband absorption based on both indium tin oxide (ITO) material and judiciously engineered metapyramid geometry. The strip ITO arrays on the sidewalls of metapyramid follow the quasi-LPDA strategy for gradient impedance and expands significantly both angular and spectral operating bandwidth by a cascading of multiple electric and magnetic resonances, as revealed by the rigorous characteristic mode analysis. Our experimental results show that the exotic absorption reaches above 0.9 at 45° tilted incidence for both transverse electric and transverse magnetic polarizations across the band of 8 ∼ 18 GHz. Our strategy circumvents the issues of limited-angle operation, high costs and high weight raised by metal structures, providing a new paradigm toward wide-angle broadband metadevices.

Kirigami-inspired metasurface has attracted great attention in electromagnetic (EM) wave manipulations, due to its unprecedented and tailorable structural transformations via mechanical approaches. However, it is still challenging for wavefront control because of its unfeasibility in forming a phase gradient at different folding angle β. Here, we report a strategy of kirigami-inspired reconfigurable phase gradient metasurfaces to efficiently control beam steering of scattering wave through mechanically changing β, where the control range of β is theoretically derived based on EM diffraction and generalized Snell’s law. For demonstration, reconfigurable anomalous reflectors with high efficiency are demonstrated in both dual-element and tri-element tunable metadevices. In former case, the reflection angle varies within 37°∼47° under polarization along y axis by changing β within the range of 10°∼40°, whereas it varies within 36°∼50° under that along x axis when β is changed within 10°∼39°, and numerical and experimental results show measured efficiency of beam steering over 78.6%. In latter case, the reconfigurable tri-element metadevice with various folding states are also experimentally characterized to further verify our strategy. Compared with available metasurfaces, our reconfigurable strategy using maneuverable structures to control EM wave is more versatile and shows great potential in engineering applications.

A super-reflector was reported to enable on-demand control of both retroreflections and reflections of circularly polarized wave. Specifically, it performs four-channel abnormal reflections at each incidence of three multiplexed spatial frequencies.

The qualitative and quantitative determination of 32 pesticide residues in surface water was established by gas chromatography-triple quadrupole mass spectrometry (GC-MS/MS). In the experiment, 32 kinds of pesticide residues were extracted at one time by optimizing the pre-treatment; and multiple qualitative ions were selected to ensure the accuracy of the results by optimizing the mass spectrometry parameters of the target compound; the unstable effect of ionization efficiency was eliminated by introducing internal standard of heptachlor B; the interference of matrix effect on pesticide residue detection was avoided by preparing standard curve of matrix. The results showed that the linear range (10~600 μg/l) of the tested residues had good linear relationship: the linear coefficient was ≥0.995, the detection limit was 0.04~0.08 μg/L, the quantitative limit was 0.2 μg/L, and the recoveries were 73.9%~108.8%. The method had the advantages of simple pretreatment, high instrument sensitivity and good selectivity, suitable for daily quantitative analysis of pesticide residues in surface water.

Objective To investigate the effects of down-regulation of long non-coding RNA-H19 (lncRNA-H19) expression on apoptosis and autophagy of human keloid fibroblast cell line and to explore potential mechanism. Methods Human scar fibroblasts cell line (KFs) and normal human dermal fibroblasts cell line (HDFs) were collected and KFs cells were infected with lncRNA-H19F low-expressing adenovirus (si-lncRNA-H19) and empty virus vector without si-lncRNA-H19 (si-eGFP). They were divided into HDFs group, KFs group, si-lncRNA-H19+KFs group and si-eGFP+KFs group. KFs cells were co-transfected with si-lncRNA, mTOR over-expressing adenovirus (Ad-mTOR) and empty vector (Ad-eGFP-m), then divided into KFs group, si-lncRNA-H19+Ad-mTOR group,si-eGFP+Ad-mTOR group, si-lncRNA-H19+Ad-eGFP group and si-eGFP+Ad-eGFP group. RT-qPCR was used to detect the expression of lncRNA-H19; flow cytometry was used to detect the cell apoptosis ; autophagy was examined by EM microscopy with fluorescence (acridine orange,AO) staining; immuno-histochemical method was used to detect the positive expression of autophagy pathway-mammalian target of rapamycin (mTOR); Western blot was used to detect the expression of apoptosis and autophagy-related proteins. Results Compared with the HDFs group, the expression of lncRNA-H19 and mTOR activity in the KFs group increased and the number of autophagic vesicles and the expression of apoptosis and autophagy-related proteins decreased (P＜0.05); after down-regulating lncRNA-H19 in KFs cells, the activity of mTOR in KFs cells decreased and apoptosis/autophagy increased (P＜0.05). Up-regulating mTOR while down-regulating lncRNA-H19 lead to more autophagy and apoptotic in KFs cells as compared to that resulted from down-regulation of lncRNA-H19 alone (P＜0.05). Conclusions Down-regulation of lncRNA-H19 expression may promote the autophagy and apoptosis of KFs cells through inhibiting activation of mTOR pathway.

Electromagnetic vortex carries the orbital angular momentum, one of the most fundamental properties of waves. The order of such vortex can be unbounded in principle, thus facilitating high-capability wave technologies for optical communications, photonic integrated circuits and others. However, it remains a key challenge to generate the high-order vortex beams in a reconfigurable, broadband and cost-effective manner. Here, inspired by the balanced-ternary concept, we demonstrate the reconfigurable generation of order-controllable vortices via cascaded N-layer metasurfaces. We theoretically showed that 3N−1${3}^{N}-1$ different vortex modes can be generated by cascading N metasurfaces, each one serving as an individual vortex beam generator for the order of 3k${3}^{k}$ (k = 0,1,2 …, N−1$N-1$). As a proof-of-concept demonstration, a reconfigurable generation of 26 different vortex beams, with orders from 1 to 13 and from −1 to −13, is showcased in a broad millimeter-wave region by a cascade of 3 metasurfaces. Our method can be easily extended to vortex beam generator of arbitrary orders in a reconfigurable and easily implementable manner, paving a new avenue towards tremendous practical applications.

Recently, reconfigurable metasurfaces have facilitated dynamic manipulation of electromagnetic (EM) waves, opening new opportunities for fascinating meta-devices. So far, most devices are working in reflection region with limited polarization states. Here, we demonstrate a reconfigurable multifunctional transmissive metasurface for both linearly and circularly polarized waves manipulations. Specifically, the designed meta-atom contains dual-layer metallic cross-strips and one-layer circular slotted patch. Eight positive-intrinsic-negative diodes are loaded between each strip structure through via hole, with each two of diodes as a group along x- and y-direction, respectively, and thus supporting four switchable states via different applied bias voltages. Numerical results indicate that the designed meta-atom achieves high-rate transmission of 0.9 and individual phase manipulation in four independent transmission channels at 7.4 GHz. As a proof-of-concept demonstration, we numerically and experimentally show different versatile functionalities, including anomalous deflections with steered beams in range of 0° ∼ 40°, orbital angular momentum generation with mode of l = 1, and beam focusing among four polarization-encoded channels at 7.4 GHz. Our metasurface owns the advantages of multi-polarization EM wave manipulations in transmission mode, which completely distinguishes from previously reported works with single polarization in reflection mode.

Metamaterials have become a promising alternative for stealth technology due to their impressive abilities to freely manipulate electromagnetic waves. With the development of radar detection technology, stringent performances are required for metamaterial absorbers (MAs), such as wideband, wide‐angle operation, and thin thickness. Herein, a systematic strategy to achieve thin broadband MAs based on trilayer indium tin oxide (ITO) resistive films with multimodes is proposed. The operation mechanism and bandwidth enhancement are analyzed and discussed in terms of the equivalent circuit model and surface current distributions. Guided by the established impedance‐gradient theory, an absorber with high‐efficiency absorption is achieved. Numerical results show that it achieves operation bandwidth (reflection loss

ZrO2/Al2O3porous ceramics were prepared by gel-foaming technique. The rheological property of slurry, the effect of solid content on the microstructure and mechanical property of the porous green bodies and the relationship between the MgO sintering additive content with the compressive strength and porosity of porous ceramics were investigated. The results show when the dispersant content is 0.4%(mass fraction), ball milling time is 4 h and the pH value is 4, the low viscosity is conductive to gelcasting. The porosity of green body reduces with the increase of solid content. The excessive solid content makes the slurry hard to flow, and the big pores and cracks form during gelcasting process, then the compressive strength of green body decreases. The mechanical properties of porous ceramics are improved with the phase transformation and micro-crack toughening induced by the ZrO2. The densification of pore supports increases, the porosity reduces and compressive strength increases with the increase of sintering additive content. The highest compressive strength is 30 MPa. The porous ceramics with appropriate porosity and high compressive strength can be prepared by introducing suitable contents of ZrO2 and sintering additive.

Abstract Electromagnetic metasurface cloaks provide an alternative paradigm toward rendering arbitrarily shaped scatterers invisible. Most transformation-optics (TO) cloaks intrinsically need wavelength-scale volume/thickness, such that the incoming waves could have enough long paths to interact with structured meta-atoms in the cloak region and consequently restore the wavefront. Other challenges of TO cloaks include the polarization-dependent operation to avoid singular parameters of composite cloaking materials and limitations of canonical geometries, e.g., circular, elliptical, trapezoidal, and triangular shapes. Here, we report for the first time a conformal-skin metasurface carpet cloak, enabling to work under arbitrary states of polarization (SOP) at Poincaré sphere for the incident light and arbitrary conformal platform of the object to be cloaked. By exploiting the foundry three-dimensional (3D) printing techniques to fabricate judiciously designed meta-atoms on the external surface of a conformal object, the spatial distributions of intensity and polarization of its scattered lights can be reconstructed exactly the same as if the scattering wavefront were deflected from a flat ground at any SOP, concealing targets under polarization-scanning detections. Two conformal-skin carpet cloaks working for partial- and full-azimuth plane operation are respectively fabricated on trapezoid and pyramid platforms via 3D printing. Experimental results are in good agreement with numerical simulations and both demonstrate the polarization-insensitive cloaking within a desirable bandwidth. Our approach paves a deterministic and robust step forward to the realization of interfacial, free-form, and full-polarization cloaking for a realistic arbitrary-shape target in real-world applications.

Recently, some advanced computer algorithms, including the inverse design method based on deep learning, have been widely applied to design versatile electromagnetic devices, featuring fast design and high efficiency especially in the global optimization problem. However, enormous amount of data generated from blind preliminary and computationally expensive simulations to predict the optical responses is required. Herein, to overcome this shortcoming of traditional deep-learning-based inverse design method, a fast, highly efficient, and sufficiently accurate synergetic strategy for devising photonic applications is presented, which integrates an explicit equivalent-circuit-intervened model as the guide in the implicit deep learning method to avoid blind calculations. As a case study of the proposed synergetic paradigm, the absorbers with customized and challenging spectral patterns are explored. For verification, three proof-of-concept designs were characterized: single-layer notched-band absorption, dual-layer trap absorption, and triple-layer ultra-wideband absorption. Our approach solves the knotty issues of batch designs, as well as the complex and time-consuming processes, suffered in traditional approaches. Moreover, our demonstrated equivalent-circuit-intervened intelligent strategy can be directly extended to various other photonic architectures, advancing a significant step toward real-world applications.