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The growing interest to develop modern digital displays and colour printing has driven the advancement of colouration technologies with remarkable speed. In particular, metasurface-based structural colouration shows a remarkable high colour saturation, wide gamut palette, chiaroscuro presentation and polarization tunability. However, previous approaches cannot simultaneously achieve all these features. Here, we design and experimentally demonstrate a surface-relief plasmonic metasurface consisting of shallow nanoapertures that enable the independent manipulation of colour hue, saturation and brightness by individually varying the geometric dimensions and orientation of the nanoapertures. We fabricate microscale artworks using a reusable template-stripping technique that features photorealistic and stereoscopic impressions. In addition, through the meticulous arrangement of differently oriented nanoapertures, kaleidoscopic information states can be decrypted by particular combinations of incident and reflected polarized light.

The miniaturization and integration of optoelectronic devices require progressive size reduction of active layers, resulting in less optical absorption and lower quantum efficiency. In this work, we demonstrate that introducing a metasurface made of hybrid organic-inorganic perovskite (HOIP) can significantly enhance broadband absorption and improve photon-to-electron conversion, which roots from exciting Mie resonances together with suppressing optical transmission. On the basis of the HOIP metasurface, a broadband photodetector has been fabricated where photocurrent boosts more than 10 times in the frequency ranging from ultraviolet to visible. The device response time is less than 5.1 μs at wavelengths 380, 532, and 710 nm, and the relevant 3 dB bandwidth is over 0.26 MHz. Moreover, this photodetector has been applied as a signal receiver for transmitting 2D color images in broadband optical communication. These results accentuate the practical applications of HOIP metasurfaces in novel optoelectronic devices for broadband optical communication.

The ability to control the instantaneous state of light, from high-energy pulses down to the single-photon level, is an indispensable requirement in photonics. This has, for example, facilitated spatiotemporal probing and coherent control of ultrafast light-matter interactions, and enabled capabilities such as generation of exotic states of light with complexity, or at wavelengths, that are not easily accessible. Here, by leveraging the multifunctional control of light at the nanoscale offered by metasurfaces embedded in a Fourier transform setup, we present a versatile approach to synthesize ultrafast optical transients with arbitrary control over its complete spatiotemporal evolution. Our approach, supporting an ultrawide bandwidth with simultaneously high spectral and spatial resolution, enables ready synthesis of complex states of structured space-time wave packets. We expect our results to offer unique capabilities in coherent ultrafast light-matter interactions and facilitate applications in microscopy, communications, and nonlinear optics.

In this study, porous Inconel 718 alloy (tetrahedral and diamond) were prepared using selective laser melting (SLM), and the compressive deformation behavior was studied. The results showed that both porous structures exhibited a linear elastic deformation stage, a plastic plateau stage, and a densification stage, which were the three stages of ductile porous materials. Tetrahedral porous structures have uneven stress distribution under compression loads, causing shear deformation. A diamond porous structure has uniform stress distribution under compression load, leading to upsetting deformation. When compared with the diamond porous structure, a tetrahedral porous structure shows better compression properties due to the reinforcement effect of the horizontal beam in the tetrahedral structure, which enhances the stiffness and strength of the material.

In this study, TiC/TC4 composites were fabricated using selective laser melting (SLM), and the deformation mechanism and fracture characteristics of the composites with nano-sized TiC particles formed in situ were studied. The experimental results showed that the rapid melting and solidification characteristics of SLM and the Marangoni effect of the liquid pool promoted a considerably homogeneous dispersion of the in situ-formed nanoscale-TiC reinforcement in the TiC/TC4 composites. In particular, an enhanced compressive strength of 1490.2 MPa and a considerable fracture elongation of 21.5% were simultaneously achieved for the TiC/TC4 composites, which could be attributed to the load transfer effect and the formation of denser and more uniformly distributed dimples. Combined with the finite element (FE) analysis, the uneven stress distribution in the shear band of the TiC/TC4 composites led to the fracture. Further, the fracture surface analysis showed that the in situ nanoscale TiC reinforcement promoted the fracture of microbubbles from the α/β interface with the concentrated distribution of the V element to the interface between TiC and the Ti matrix because of the load transfer, which promoted the uniform distribution of the V element in the dimple.

Surface plasmon polaritons (SPPs) are electromagnetic waves that travel along a metal–dielectric interface and are finding an ever-increasing number of applications in newly emerging nano-photonic and optoelectronic technologies. Different from the traditional approach to excite SPPs using prism or grating, metallic metasurfaces incorporating nano-slots with different orientations enable the photonic spin-dependent directional coupling of SPPs, which shows the unique spin tunability. However, the propagations of these generated SPPs are still correlative due to the conjugated phase profiles of metasurfaces for two incident orthogonal spin states. Here, we propose a plasmonic spin-multiplexing metasurface composed of nano-slots with different geometric dimensions and orientations to efficiently control the near-field generation and in-plane propagation of SPPs. By taking into account both the geometric phase and resonant phase of the nano-slots, the metasurface can generate two independent and fully decoupled SPP fields for a pair of orthogonal spin states. As proof-of-concept, we design a series of spin-multiplexing metasurfaces to numerically demonstrate different near-field optical functionalities, including spin-controlled plasmonic bi-focusing, self-accelerating beams, and vortices. We envision this approach may have potential applications in designing polarization-dependent tunable plasmonic nano-devices.

The term Poincaré beam, which describes the space-variant polarization of a light beam carrying spin angular momentum (SAM) and orbital angular momentum (OAM), plays an important role in various optical applications. Since the radius of a Poincaré beam conventionally depends on the topological charge number, it is difficult to generate a stable and high-quality Poincaré beam by two optical vortices with different topological charge numbers, as the Poincaré beam formed in this way collapses upon propagation. Here, based on an all-dielectric metasurface platform, we experimentally demonstrate broadband generation of a generalized perfect Poincaré beam (PPB), whose radius is independent of the topological charge number. By utilizing a phase-only modulation approach, a single-layer spin-multiplexed metasurface is shown to achieve all the states of PPBs on the hybrid-order Poincaré Sphere for visible light. Furthermore, as a proof-of-concept demonstration, a metasurface encoding multidimensional SAM and OAM states in the parallel channels of elliptical and circular PPBs is implemented for optical information encryption. We envision that this work will provide a compact and efficient platform for generation of PPBs for visible light, and may promote their applications in optical communications, information encryption, optical data storage and quantum information sciences., Well-controlled Poincaré beams are potentially useful in optical communications applications. Here, the authors present phase-only metasurfaces that generate broadband, perfect Poincaré beams in the visible, with radius independent of the topological number.

Display and power supply have been two essential and independent cornerstones of modern electronics. Here, we report a lithium-plasmon-based low-powered dynamic color display with intrinsic dual functionality (plasmonic display and energy recycling unit) which is a result of the electric-field-driven transformation of nanostructured lithium metals. Dynamic color displays are enabled by plasmonic transformation through electrodeposition (electrostripping) of lithium metals during the charging (discharging) process, while the consumed energy for coloring can be retrieved in the inverse process respectively. Energy recycling of lithium metals brings energy consumption down to 0.390 mW cm−2 (0.105 mW cm−2) for the active (static) coloration state of a proof-of-concept display/battery device, which approaches nearly-zero-energy-consumption in the near-100%-energy-efficiency limit of commercial lithium batteries. Combining the subwavelength feature of plasmonics with effective energy recycling, the lithium-plasmon-based dynamic display offers a promising route towards next-generation integrated photonic devices, with the intriguing advantages of low energy consumption, a small footprint and high resolution.

A graphene (Gr)/Ti6Al4V composite coating was prepared by laser cladding, and the microstructure and the properties were studied. The results showed that an in situ synthesis between Gr and Ti occurred and TiC was formed. The TiC was homogeneously distributed. The α’ acicular martensite was formed at the bottom of the coating during the rapid solidification process, and a good metallurgical bond was formed between the coating and substrate. The TiC and the self-lubrication of Gr improved the wear resistance of coating. And the wear mechanism changed from more serious abrasive and adhesive wear to a mild wear with fine scratches. Meanwhile, severe oxidative wear occurred in the coating and substrate under high-temperature friction and wear. The corrosion resistance of the coating was also improved. The corrosion morphology changed from denudation and pitting to local pitting. The Gr and TiC in the coating effectively preventeds the corrosion.

TiC/316L stainless steel composite was prepared by selective laser melting (SLM). The effects of alloying elements X (Cr, Mn, Mo, Ni, Si) in 316L stainless steel on the stability of TiC (001)/γ-Fe (001) interface were calculated by the first principle. The results showed that alloy elements easily replace the Fe atom at the interface, and all of them have the tendency to segregate to the interface. The adhesion work, bond length, interlayer distance, and electronic properties were calculated; it was found that the interface models of Cr4, Mn4, Mo4, Ni1, and Si1 are more conducive to improve the interface bonding strength, and the Cr-, Mn-, and Mo-doped interfaces are more stable than other interfaces. Both X1 and X4 structures represent the doping of an alloy atom but only in different crystallographic sites. Therefore, the introduction of Cr, Mn, Mo, Ni, and Si will promote the heterogeneous nucleation of Fe on TiC and enhance the heterogeneous nucleation potential of TiC and improve the interfacial bonding strength of TiC/316L stainless steel composite. Effects of alloying elements on the interface stability and electronic density of TiC (001)/γ-Fe (001)

Polarimetry, refers to the measurement of polarization states, has triggered vital applications in polarization imaging, biological sensing, and quantum optics. Traditional polarimetry has been well established to characterize polarization states but with bulk optical elements. With the development of micro- and nano-optics, a polarimetry device with ultracompact architecture is highly on-demand. Herein, a silicon metasurface-based full-Stokes polarimetry device for long-wavelength infrared light is proposed and experimentally demonstrated. The metasurface is composed of silicon micropillar array, each of which can be regarded as a micro-scale birefringent wave-plate. Through a polarization-dependent phase profile design, the metasurface has the ability to split and focus different polarization states and, thus, is capable of achieving full-Stokes polarimetry. The demonstrated strategy holds the potential applications for infrared polarization detection and imaging in compact systems.

With the development of high-performance supercapacitors, a conductive polymer (CP)-based pseudocapacitance electrode with good electrical conductivity and low processing costs holds a promising application prospect. As the core component of supercapacitors, the CP electrode with adjustable spacing, a high specific surface area, and a faster ion diffusion path has been extensively investigated. Herein, based on accurate top-down photolithography and electropolymerization approaches, we fabricate a CP-coated vertically aligned micropillar array (MPA) electrode. The electrode presents an overwhelming enhanced areal specific capacitance compared with that of a flat configuration, which is partially ascribed to an increased electroactive surface area, two rapid channels for ion diffusion and electron transfer, and enhanced electric field intensity that is provided by the MPA structure. Based on the fabricated CP-based MPA electrode, an asymmetric supercapacitor is assembled with two thiophene derivatives, presenting a high energy density and excellent cycling stability. A supercapacitor system cascading with three asymmetric supercapacitor devices further demonstrates the practical applications by driving the light-emitting diodes. This work provides a good reference for the further development of CP-based energy storage devices with high energy density and superior cycling stability.

Arbitrary spatiotemporal shaping requires complete control of the electric-field vector at each space-time coordinate. Here, we demonstrate simultaneous and independent tailoring of spatial and temporal properties of femtosecond pulses using a single-layer dielectric metasurface.

Porous TC4 alloy scaffolds with curved struts were fabricated by selective laser melting (SLM), and the compression deformation behavior of the TC4 alloy scaffolds was studied. When the porous scaffold is compressed along the direction of the building, the stress of the porous scaffold first increases sharply with the increase in the strain, then decreases rapidly and finally shows a stepped increasing trend. Combined with the finite element method and uniaxial compression experiments, the shear position of porous scaffold takes precedence over other parts, and the fracture mainly occurs on the strut near the joint of the porous scaffold. The fracture surface analysis shows that the joint is a ductile fracture, and there is a shallow “dimple” pattern of shear or tear type on the fracture surface, while the fracture morphology of the strut near the joint of porous TC4 alloy scaffold is relatively smooth, which is a typical brittle fracture. The mixed fracture mode is caused by the more concentrated stress at the strut than the joint and the hexagonal close-packed (hcp) fine martensite α′ formed by the SLM.

Monochromatic light can be characterized by its three fundamental properties: amplitude, phase, and polarization. In this work, we propose a versatile, transmission-mode all-dielectric metasurface platform that can independently manipulate the phase and amplitude for two orthogonal states of polarization in the visible frequency range. For proof-of-concept experimental demonstration, various single-layer metasurfaces composed of subwavelength-spaced titanium-dioxide nanopillars are designed, fabricated, and characterized to exhibit the ability of polarization-switchable multidimensional light-field manipulation, including polarization-switchable grayscale nanoprinting, nonuniform cylindrical lensing, and complex-amplitude holography. We envision the metasurface platform demonstrated here to open new possibilities toward creating compact multifunctional optical devices for applications in polarization optics, information encoding, optical data storage, and security.

Optical polarization topology is a spatially varying polarization structure, which usually exists around the polarization singularity. In three-dimensional (3D) space, optical polarization topologies mainly contain two fundamental structures, Möbius strip and twisted ribbon, depending on the parity of half-twist number. These spectacular topologies have been widely found in the existence of electric fields from multi-beam interference. Here, we propose and numerically demonstrate that, depending on the photonic spin state of light, an ultrathin all-dielectric metasurface can achieve efficient generation and transformation of two arbitrary 3D polarization topologies. The spin-controlled, tightly-focused Poincaré beams generated by the metasurface exhibit topologically stable 3D polarization topologies around the waist of the focal point. The preparation of such optical polarization topologies may have potential applications in compact complex beam engineering, optical signal multiplexing and optical fabrication of microstructures with nontrivial topology.

Bending light along arbitrary curvatures is a captivating and popular notion, triggering unprecedented endeavors in achieving diffraction-free propagation along a curved path in free-space. Much effort has been devoted to achieving this goal in homogeneous space, which solely relies on the transverse acceleration of beam centroid exerted by a beam generator. Here, based on an all-dielectric metasurface, we experimentally report a synthetic strategy of encoding and multiplexing acceleration features on a freely propagating light beam, synergized with photonic spin states of light. Independent switching between two arbitrary visible accelerating light beams with distinct acceleration directions and caustic trajectories is achieved. This proof-of-concept recipe demonstrates the strength of the designed metasurface chip: subwavelength pixel size, independent control over light beam curvature, broadband operation in the visible, and ultrathin scalable planar architecture. Our results open up the possibility of creating ultracompact, high-pixel density, and flat-profile nanophotonic platforms for efficient generation and dynamical control of structured light beams.

The effect of heat treatments (solution and double aging) on friction and wear behaviour of Inconel 718 (IN718) alloy fabricated by selective laser melting (SLM) were studied. After heat treatment ...

We demonstrate arbitrary control of femtosecond timescale complex electrical-field transients using dielectric metasurfaces, enabling temporal vectorial ultrafast pulses with rich instantaneous polarization states and a simultaneously tailored spatial wavefront.

A dielectric-metasurface-enabled pulse shaper able to tailor the temporal instantaneous polarization states within a near-infrared femtosecond pulse is demonstrated. Simultaneous complex wavefront shaping has been implemented by exploiting metasurfaces’ multi-functionalities within a single-pixel.

Dielectric metasurfaces enable control of the temporal profile of large bandwidth, near-infrared femtosecond pulses. Using this approach, we demonstrate shaping of the time-domain polarization state within a single pulse.

We demonstrate a dielectric-metasurface-enabled pulse shaper able to tailor the temporal polarization of near-infrared femtosecond pulses over an ultrawide bandwidth, allowing three-dimensional vector-shaped pulses exhibiting rich time-evolving instantaneous polarization states within a single pulse.

We realize a dielectric metasurface that enables full-color generation and ultrasmooth brightness variation. The reproduced artwork “girl with a pearl earring” features photorealistic color representation and stereoscopic image impression, mimicking the texture of an oil-painting.

Dielectric metasurfaces enable control of the temporal profile of large bandwidth, near-infrared femtosecond pulses. Using this approach, we demonstrate shaping of the time-domain polarization state within a single pulse.

In this study, in situ-formed TiC/TC4 alloy nanocomposites were fabricated using the selective laser melting (SLM) process with TC4 and graphene nanoplates (GNPs) powders, and the deformation strengthening mechanism of the Ti matrix reinforced with TiC nanoparticles was investigated. The results from microstructure observation and molecular dynamics simulations revealed that the appearance of nanoscale TiC reinforcement favoured the formation of deformation twinning, which promoted that the atoms of the TiC/TC4 alloy nanocomposites maintained an orderly arrangement during deformation. Further, a dual strengthening mechanism of that the severe lattice distortion at the interface formed by different orientations and the deformation twinning suppressed the movement of the dislocation has been put forward to describe the occurring of dislocation pinning effects. All these findings provide a feasible perspective to strengthen mechanical performance by addressing the long-standing issue in the SLM of TC4 alloy nanocomposites.

Objective Type 2 diabetes mellitus (T2DM) is a complex disease influenced by genes and the environment. Periodontitis a demonstrated risk factor of T2DM. Previous studies related to gene-environment interactions on the risk of T2DM mainly focused on gene-obesity interactions. However, the impact of gene-periodontitis interaction on the risk of T2DM has not yet been investigated. This study aimed to investigate gene-environment interactions among moderate/severe periodontitis, polymorphisms of adiponectin (ADIPOQ)-rs1501299, and leptin receptor (LEPR)-rs1137100 on T2DM risk in Chinese subjects. Design A case-control study was conducted in 239 Chinese participants from Beijing Hypertension Association Institute (BHAL). After full-mouth periodontal examinations, the participants underwent bilateral buccal swabs for DNA testing. ADIPOQ-rs1501299 and LEPR-rs1137100 were used for genotyping. Generalised multifactor dimensionality reduction (GMDR) and logistic regression were used to examine the interactions among single nucleotide polymorphisms (SNPs) and moderate/severe periodontitis on the risk of T2DM. Results The risk of T2DM was higher in moderate/severe periodontitis [adjusted odds ratio (AOR) = 3.67, 95% confidence interval (95%CI): 1.26–10.71] in ADIPOQ-rs1501299 GG genotype (AOR = 3.42, 95%CI: 1.81–6.46) and LEPR-rs1137100 GG genotype (AOR = 3.16, 95%CI: 1.56–6.39). The GMDR model indicated that there was a significant three-factor model (p = 0.001) involving rs1501299, rs1137100, and moderate/severe periodontitis, demonstrating a potential gene-environment interaction among periodontitis, polymorphisms of rs1501299, and rs1137100 influencing the risk of T2DM. Moderate/severe periodontitis patients with rs1501299-GG and rs1137100-GG have the highest T2DM risk after adjusting for age, gender, BMI, WHR, smoking status, alcohol consumption, economic status, and hypertension (AOR = 20.39, 95%CI: 2.64–157.26). Conclusions Interactions among moderate/severe periodontitis, rs1501299-GG, and rs1137100-GG were associated with an increased risk of T2DM. This study may provide a new insight into the effect of gene-environment interactions on T2DM.

This research explored a novel chemical reduction of organic aluminum for plating Al on a graphene surface. The thermodynamics of the Al plating reaction process were studied. The Al plating process consisted of two stages: the first was to prepare (C2H5)3Al. In this reaction, the ΔH(enthalpy) was 10.64 kcal/mol, the ΔG(Gibbs free energy) was 19.87 kcal/mol and the ΔS(entropy) was 30.9 cal/(mol·K), this was an endothermic reaction. In the second stage, the (C2H5)3Al decomposed into Al atoms, which were gradually deposited on the surface of the graphene and the Al plating formed. At 298.15 K, the ΔH was −20.21 kcal/mol, the ΔG was −54.822 kcal/mol, the ΔS was 116.08 cal/(mol·K) and the enthalpy change was negative, thus indicating an endothermic reaction.

Color is a primary attribute of human visual perception and plays a crucial role both in imaging and display technology and in the arts. In work this year, we demonstrated the ability to tune both color hue and brightness in transmitted light with a specially designed metasurface—at a level of detail sufficient to create a “nanopainting” that reproduces a celebrated artwork.

Light beams carrying spin angular momentum (SAM) and orbital angular momentum (OAM) have created novel opportunities in the areas of optical communications, imaging, micromanipulation and quantum optics. However, complex optical setups are required to simultaneously manipulate, measure and analyze these states, which significantly limits system integration. Here, we introduce a novel detection approach for measuring multiple SAM and OAM modes simultaneously through a planar nanophotonic demultiplexer based on an all-dielectric metasurface. Coaxial light beams carrying multiple SAM and OAM states of light upon transmission through the demultiplexer are spatially separated into a range of vortex beams with different topological charge, each propagating along a specific wavevector. The broadband response, material dispersion and momentum conservation further enable the demultiplexer to achieve wavelength demultiplexing. We envision the ultracompact multifunctional architecture to enable simultaneous manipulation and measurement of polarization and spin encoded photon states with applications in integrated quantum optics and optical communications.

In order to improve the wear resistance of aluminum alloys and expand its applications, the microstructure and tribological properties of nano-graphene reinforced aluminum matrix composites—which were fabricated by selective laser melting (SLM)—were investigated. Experiments were conducted to investigate the effect of slide speeds (0.3–0.9 m/s) and normal loads (10N–30N), which demonstrated the dislocation strengthening and load strengthening resulting from the homogeneous dispersion of graphene nano-platelets (GNPs) enhance the wear resistance of GNPs/AlSi10Mg composites. With the increase of slide speed, the wear rate of composites decreases and the wear regime changes from abrasive wear to delamination wear, which is because the formation of a relatively stable mechanically mixed layer (MML) reduces the contact area between the counterbody material and the wear surface, and the nano-graphene bridges between the subsurface cracks improve the tribological performance. Meanwhile, with the increase of normal load, the predominant wear regime of the reinforced composite is the combination of delamination wear and oxidize wear. And the coefficient of friction (COF) decreases as the slide speed increases, which is because the self-lubricating property of graphene nano-platelets makes it easy to form interlayer sliding and reduce friction effectively.

Application of traditional bait in freshwater aquaculture caused environment pollution and disease frequent occurrence. Effluent after Rubrivivax gelatinosus ATCC 49846 (R. gelatinosus) wastewater treatment could be re-utilized to culture Crucian carp as microbial feeds and aquaculture water. Therefore, a novel integrated system of wastewater treatment, the improvement of yield, digestion system, intestinal microbiota and aquaculture water quality of Crucian carp by effluent containing R. gelatinosus was proposed and investigated. Crucian carp could grow well in the effluent containing immobilized cells of R. gelatinosus ATCC 49846 in sodium alginate (ER) group. Survival rate and yield under ER group were almost same with control group (CK). The whole fish body composition under ER group were increased compared with CK. Biochemicals and remainder substances in effluent and R. gelatinosus enhanced protease, amylase, lipase activities. Theoretical analysis showed biochemical substances regulated these enzyme activities as component, active center. Moreover, R. gelatinosus and biochemical substances improved intestinal microbiota, the growth of intestinal probiotics and ATP production. Meanwhile, R. gelatinosus in effluent also purified aquaculture water quality. This technology would saved the water of aquaculture, reduced the water pollution and wastewater discharge, and improved the output, digestion system and intestinal microbiota of Crucian carp simultaneously.

The magnetic nanoparticle (NP) chain has attracted great concern due to its potential applications in magnetic recording, electron nano-devices, micro-mechanical sensors, and drug delivery. Here, we demonstrate the controllable preparation of magnetic Ni NP chains using electrochemical corrosion methods. Ni/Cu multi-segmented nanowires (NW) were prepared by alternately depositing Ni and Cu into the pores of an anodic aluminum oxide (AAO) template, then highly uniform Ni NP chains were obtained by immersing Ni/Cu NWs/AAO composite membrane in a 15 wt% NaOH solution for about 50 min. The reaction mechanism is proposed based on electrochemical corrosion, in which Cu serviced as the anode is corroded and Ni serviced as the cathode are retained in the NaOH electrolyte solution. Particle size and separation of the Ni NP chains can be easily adjusted and the smallest particle size and particle spacing reached to 6 nm and 15 nm, respectively. This strategy developed herein can be expected to be general route for the controllable fabrication of metallic NP chains.