33 results about "Metamaterial absorber" patented technology

Wireless devices are commonly carried in fabric-based apparel. Printing metamaterial structures on fabric substrates allows for the ability to create fabric metamaterial layers. A reconfigurable RF based fabric system simply by physically removing or adding different fabric-based metamaterial layers to different regions of the apparel. The fabric-based metamaterial can be used in various filtering applications where the control of phase, reflection angle, refraction angle, polarization, absorption, and transmission of the impinged electromagnetic wave can all be manipulated. Additionally, sophisticated metamaterial systems can be created by combining different metamaterial layers separated above each other. A controllable absorber metamaterial system can be made consisting of two layers. The first layer an electronically controllable that can controllably change between a band-pass and band-reject filter in a relevant frequency band and a second absorptive layer. Vehicles with adjustable metamaterial absorber systems, integrated on the outside or inside of the RF transparent fuselage, have the ability to control their radar cross section dynamically for the purposes of evading detection or spoofing their size by looking larger or similar to vehicles of different radar cross section.

An infrared detector includes a tuning fork resonator comprising an mechanical-to-electrical transduction mechanism; a metamaterial absorber residing on at least one side of the tuning fork resonator, the metamaterial absorber comprising at least a material layer with subwavelength inclusions; and a signal processing circuit to translate the electrical signal into an amplitude of mechanical motion of the tuning fork.

The application provides a light-weight broadband metamaterial wave-absorbing structure based on a C-shaped sandwich structure, which comprises a first composite layer, a second composite layer and a reflecting layer arranged in sequence along the electromagnetic wave propagation direction; the first composite layer comprises a sandwich structure composed of multiple wave-transparent layers and skin layers arranged alternately; the second composite layer comprises a resistance film layer and a wave-transparent dielectric layer arranged alternately; and the lowermost wave-transparent dielectric layer is provided with the reflecting layer on the lower surface. The C-shaped sandwich structure can greatly improve the wave-absorbing performance of the wave-absorbing sandwich structure in the high-frequency (Ku) band, and overcomes the shortcoming that when the skin is thicker than 0.5 mm, the wave-absorbing sandwich structure is difficult to obtain satisfactory wave-absorbing effect in the high-frequency (Ku) band.

This invention discloses a wide-bandwidth, wide-angle metamaterial microwave absorber covering the L, S, C, X, and Ku bands, belonging to the field of stealth technology. The unit structure of the microwave absorber includes an upper FR4 plate with three-dimensional printed high-resistivity carbon paste, a middle paper honeycomb support layer, and a bottom magnetic material attached to a metal plate. The upper FR4 plate provides microwave absorption performance at mid and high frequencies, while the bottom magnetic material provides microwave absorption performance at low frequencies. The two are fixed by the paper honeycomb of the middle support layer. By combining a three-dimensional microwave absorber with magnetic materials, this invention achieves wide-bandwidth, wide-angle microwave absorption performance. The composite microwave absorber structure constructed by this invention has high structural strength and achieves lightweight design.

The invention relates to the technical field of metamaterial absorbers, and particularly discloses a multifunctional far-infrared metamaterial absorber based on graphene and Dirac semimetal and a preparation method of the multifunctional far-infrared metamaterial absorber based on graphene and Dirac semimetal. Each metamaterial unit is of a laminated structure and sequentially comprises a Dirac semimetal layer, a graphene layer, a dielectric layer and a metal reflecting layer from top to bottom. The Dirac semimetal layer is in a rudder shape and comprises a square structure with the center being a hollow cylinder, a cylinder structure and four rectangular structures, the cylinder structure is arranged outside the square structure, the square structure and the cylinder structure are concentrically arranged, the four rectangular structures are evenly distributed outside the square structure, and the cylindrical structure is arranged outside the square structure. And the four rectangular structures are respectively and vertically intersected with the side surfaces of the square structure. The far infrared metamaterial absorber has tunable multi-peak absorption and has the broadband and narrowband dynamic switching capability, and the device structure is easy to prepare.

The invention relates to the technical field of microfluidics, in particular to a light-heat-sound microflow pump based on a metamaterial absorber and a preparation method of the light-heat-sound microflow pump. The technical key points are as follows: a bottom metal film, a dielectric layer and a top metal structure array are sequentially formed on a substrate to prepare the metamaterial absorber chip with the plasmon photothermal effect; spin-coating the metamaterial absorber chip with polydimethylsiloxane, and carrying out drying and curing treatment to obtain the metamaterial absorber chip with a light-taking effect; the optical-thermal-acoustic micro-flow pump with the fluid driving and mixing capabilities can be obtained by irradiating the metamaterial absorber chip with the optical effect by using laser, non-contact, remote and high-precision driving of micro-fluid is realized, and the optical-thermal-acoustic micro-flow pump has the technical effects of simple structure, high driving efficiency, high response speed and no need of complex external equipment.

The utility model relates to far infrared metamaterial absorber technical field, specifically disclose a multifunctional far infrared metamaterial absorber, including a plurality of periodic array arrangement's metamaterial unit, the metamaterial unit is for the laminated structure, from top to bottom includes successively: dirac half metal layer, graphene layer, dielectric layer, metal reflection layer, the dirac half metal layer is rudder -shaped, including center hollow cylinder's square structure, cylinder structure, four rectangle structure, the cylinder structure is located the outside of square structure, square structure, cylinder structure concentric arrangement, four rectangle structures evenly distribute in the outside of square structure, four rectangle structures respectively with square structure side vertical intersection. The far infrared metamaterial absorber of the application has tunable multi-peak absorption characteristic, and has wideband and narrowband dynamic switching ability.

The invention provides a broadband metasurface wave absorber based on an oblique symmetric mosaic structure. The broadband metasurface wave absorber comprises a metal resonance layer, a dielectric layer and a metal reflecting layer which are sequentially stacked, the metal reflecting layer is formed by two inlaid structures which are arranged in an oblique symmetry mode, each inlaid structure comprises a semi-square ring body and a semi-circular ring body wrapping the outer side of the semi-square ring body, and two edge protruding edges of each semi-square ring body are connected with the corresponding semi-circular ring body; the semi-square ring body and the semi-circular ring body are both of an open structure, and the opening directions of the semi-square ring body and the semi-circular ring body are the same. According to the wave absorber disclosed by the invention, a broadband absorption effect on electromagnetic waves in a frequency band of 9.43 GHz to 14.95 GHz is realized; meanwhile, within the absorption frequency band, the absorption rate of electromagnetic waves reaches 90% or above, and the absorption rate of electromagnetic waves reaches 99% or above near two resonance peak values of 10.02 GHz and 13.56 GHz.

The application provides a chiral metamaterial absorber for multifunctional sensing and a preparation method thereof, and relates to the technical field of optics.The absorber comprises a periodically arranged three-dimensional double-layer unit structure, each unit structure sequentially comprises a Z-shaped chiral metal layer and a temperature-sensitive semiconductor layer from top to bottom; the material of the Z-shaped chiral metal layer is gold; the material of the temperature-sensitive semiconductor layer is indium antimonide, the dielectric constant of which dynamically changes with temperature, thereby realizing active regulation of circular dichroism in the terahertz wave band.The application realizes strong chiral selective absorption in the terahertz wave band through the periodic three-dimensional structure of the Z-shaped chiral metal layer and the temperature-sensitive semiconductor layer, and has high-sensitivity temperature sensing at 300K-360K and a wide-range refractive index of 1.0-2.0, and high-quality factor guarantees efficient integrated functions.

This invention proposes a multi-mode fusion, high-ratio, independent dual-band metamaterial absorber, which consists of K×K periodically arranged resonant units. Each resonant unit includes a top frustum-shaped integrated absorption structure and a bottom Helmholtz resonant cavity absorption structure. The frustum-shaped integrated absorption structure comprises a square first dielectric substrate, a square second dielectric substrate, and metal patches printed on their surfaces. The bottom Helmholtz resonant cavity includes two rectangular slots intersecting in a cross shape on the upper surface of a square cubic metal structure, and a triangular prism cavity with an isosceles triangular cross-section located inside the cubic metal structure, penetrating its front, back, left, and right sides. The rectangular slots and the triangular prism cavity are filled with dielectric material. This invention achieves dual-band absorption by combining the Helmholtz resonant mode and the frustum-shaped integrated absorption mode, and improves the absorption ratio of the dual-band absorption. It can be used in the field of decoupling high-ratio dual-band antenna arrays.

A selective metamaterial absorber and method for fabricating the same is disclosed. The method includes deposing a first metal layer on a first surface of a substrate and on a plurality of nanowires extending outward from the first surface of the substrate, the plurality of nanowires forming an array on the first surface, the substrate further including a second surface opposite the first surface. The first metal layer may be deposed using conformally sputtering. The substrate and the plurality of nanowires may be composed of silicon, and the first metal layer may be composed of tungsten. The first metal layer may be composed of a material having a penetration depth for a wavelength range of interest. The first metal layer may be at least three times thicker than the penetration depth.

In some implementations, a metamaterial absorber (MMA) is configured to absorb a particular range of electromagnetic radiation. The MMA includes a first metal or semiconductor material; a dielectric material disposed on the first metal or semiconductor material; and a second metal material disposed on the dielectric material. A length dimension associated with the MMA is less than or equal to 200 micrometers (μm), a width dimension associated with the MMA is less than or equal to 200 μm, and a thickness dimension associated with the MMA is less than or equal to 8 μm.

This application discloses an ultra-wideband high-isolation transceiver array, belonging to the field of antenna technology. The ultra-wideband high-isolation transceiver array embeds a dual-polarized transmitting array and a dual-polarized receiving array within a first metal cavity and a second metal cavity, respectively. The surface of the metal platform is provided with multiple metamaterial absorber groups with multi-layered multi-resonant unit structures, wherein each metamaterial absorber group is periodically arranged. The apertures of both the dual-polarized transmitting and receiving arrays are chamfered at 45° to concentrate the energy of the sidelobes of each array onto the diagonally opposite region of the array aperture, thereby improving the isolation between the dual-polarized transmitting and receiving arrays.

The invention discloses an optimization design method for a multi-band coupling metamaterial absorber structure, and relates to the technical field of metamaterial design, and the method comprises the steps: firstly, obtaining a structure parameter set and a structure parameter constraint set of an absorber basic unit; then, according to the structure parameter set and the structure parameter constraint set of the absorber basic unit, taking maximization of a first index and a second index corresponding to each target frequency as an optimization target, and utilizing a non-dominated sorting genetic algorithm to solve and obtain an optimal structure parameter value set; the first index corresponding to each target frequency refers to the reciprocal of the distance between the resonant frequency of the first resonant peak and the target frequency; the second index corresponding to each target frequency refers to the absorptivity of the first harmonic peak. According to the method, the non-dominated genetic algorithm is introduced into the metamaterial structure design, so that the difficulty of the metamaterial structure design is reduced, and the efficiency of the metamaterial structure design is improved.

This invention discloses a broadband metamaterial absorber based on a swastika shape, comprising multiple absorbing units, each including a reflective layer; a dielectric substrate disposed on the reflective layer; and an ITO thin film resonant layer disposed on the dielectric substrate. The resonant layer has a cross-shaped structure. First extensions extend from the four ends of the resonant layer, making it swastika-shaped. Second extensions extend perpendicularly from the four first extensions, and the first and second extensions connect to form a corner structure. The circuit resonance in this invention is stable. When the surface impedance matches the free-space impedance within a wide bandwidth, electromagnetic waves of different frequencies can effectively enter the absorber and be absorbed, achieving broadband absorption. The addition of a corner structure to the resonant layer not only increases the length of the current path, thereby increasing the equivalent inductance, but also increases the propagation path length of electromagnetic waves within the metamaterial, thus broadening the absorption bandwidth.

The invention relates to the technical field of electromagnetic wave absorption, and discloses a stacked annular water-based metamaterial absorbing material with a scattering characteristic and a process thereof, the material is composed of periodically arranged unit structures, each unit structure comprises a metal substrate, a structure support body arranged on the metal substrate and a liquid absorbing medium filled in the metal substrate, the structure supporting body is integrally formed by a photosensitive resin material, and a three-dimensional water cavity structure formed by vertically stacking or combining various geometrical shapes such as a cross shape, a cylinder shape, a ring shape or an open ring shape is formed in the structure supporting body. According to the structural design, multiple resonance modes can be excited under electromagnetic wave incidence, a wide absorption frequency band is formed through coupling and superposition of the multiple resonance modes, the invention further discloses a preparation process of the structure, the structure supporting body is manufactured through the 3D printing technology, and then liquid filling and overall assembling are conducted. The problem that the bandwidth of an existing absorbing material is limited is solved, the preparation process is simple, and the cost is low.

The invention relates to a three-band metamaterial wave absorber based on artificial intelligence aided design, and belongs to the technical field of artificial electromagnetic materials. The invention aims to solve the problems of low absorption efficiency, narrow bandwidth, large thickness and sensitivity to incident wave polarization state of the traditional wave-absorbing material. The wave absorber adopts a periodically arranged array unit structure, each unit is composed of a metal resonance layer, a dielectric layer and a metal back plate from top to bottom, and the metal resonance layer comprises two coaxial closed resonance rings and four 90-degree fan-shaped metal patches which are symmetrically distributed. Structural size parameters are optimized through an artificial intelligence aided design method, the advantages of three-band high absorptivity, polarization insensitivity, ultra thinness and compactness are achieved, and the sensor has the remarkable effects of being simple in structure, low in cost and easy to manufacture and is suitable for high-performance electromagnetic wave absorption and sensing application.

This invention discloses a high-temperature resistant, high-absorption ceramic superatom and its preparation method. The high-temperature resistant, high-absorption ceramic superatom is obtained by high-precision wire cutting of millimeter-wave dielectric ceramic, the composition of which is Ba4Nd. 9.33‑ x Sm x Ti 18‑y Co y O 54‑δ In the formula, x is 3-6, y is 2-3, and δ is 1-1.5. The ceramic superatomic structure provided by this invention is simple and compact, with high temperature stability and tolerance. It is compatible with metamaterial absorbers of different millimeter-wave frequencies and can meet the application requirements of miniaturization, multi-scenario, and especially extreme scenarios of current millimeter-wave technology.

The invention discloses a switchable metamaterial absorber based on vanadium dioxide and graphene and a dynamic tuning method, and relates to the technical field of terahertz wave devices. The absorber is formed by continuously splicing periodic unit structures on a plane in an array form, and each periodic unit structure is sequentially provided with a vanadium dioxide-graphene composite metasurface, a dielectric layer and a metal reflecting layer from top to bottom; the vanadium dioxide-graphene composite metasurface is composed of a patterned graphene disc and three fan-shaped structure vanadium dioxide layers distributed around the graphene disc in the circumferential direction, the insulation-metal phase change state of vanadium dioxide and the Fermi level of graphene are regulated and controlled through external excitation, and flexible switching between broadband absorption and double-narrow-band absorption can be achieved. The absorber has the advantages of being compact in structure, easy and convenient to prepare, insensitive to polarization and the like, has excellent dynamic tuning performance and wide-angle stability, and has integration and multifunctional application prospects in the fields of terahertz communication, imaging, biosensing, environment monitoring and the like.

This invention relates to a tunable narrowband metamaterial absorber belonging to the fields of metamaterial absorbers and terahertz technology. The tunable narrowband metamaterial absorber is composed of an array of multiple identical absorber units. Each absorber unit is arranged from top to bottom with a strontium titanate layer (1), a dielectric layer (2), and a gold film (3). The length and width of the strontium titanate layer (1), the dielectric layer (2), and the gold film (3) are identical. A rectangular blind hole is etched on the absorber unit, penetrating the strontium titanate layer (1) to the upper surface of the dielectric layer (2). At the bottom of the rectangular blind hole, a graphene layer (4) is tightly attached to the upper surface of the dielectric layer (2). This tunable narrowband metamaterial absorber has dual-control functionality and is insensitive to polarization. By changing the Fermi level of the graphene layer, the absorption rate can be controlled; by changing the ambient temperature of the strontium titanate layer, the center frequency can be controlled.

The present application relates to the technical field of electromagnetic wave absorbing material, and proposes a metamaterial absorber in full terahertz wave band and a preparation method thereof; the moth-eye array three-phase absorber is arranged and combined by unit structures periodically, each unit is composed of a metal reflection bottom plate, a dielectric / loss layer and a resonance layer, wherein the resonance layer is a hollow cone VO2 array with gradually changing parameters along the z-axis, and the dielectric / loss layer is a metalized resin; after the unit geometry and material parameters are optimized based on electromagnetic simulation software, surface projection microstereolithography and template method are adopted to form step by step: the VO2 cone shell is obtained by template transfer, the resin layer is directly printed and liquid metal is poured under negative pressure, and finally the device is stacked in sequence with the Cu reflection layer; the directional forming and accurate alignment of VO2 and resin can be realized in the micron scale, the device is small in thickness, the process can be enlarged, more than 90% wideband high absorption can be realized in the full terahertz frequency band of 0.8-10 THz, the structure has strong designability, good preparation consistency, is not sensitive to wide incidence angle and polarization, and the like.

The invention provides a frequency-adjustable electromagnetic metamaterial wave absorber based on radial shrinkage. The wave absorber comprises a plurality of wave absorbing units which are distributed in an array mode. Each wave absorbing unit comprises a unit substrate, a reflecting layer, a resonance device and a driving mechanism; the reflecting layer is arranged on one surface of the unit substrate, a mounting groove is formed in the other surface of the unit substrate, and the resonant device is movably arranged in the mounting groove; the driving mechanism is used for driving the resonance device to move in the installation groove in the radial direction. According to the invention, by adjusting the radial displacement of the resonance device, the dynamic adjustment of the pattern shape of the metamaterial unit is realized, the optimized wave absorption can be realized for different polarization threats, and the reflection coefficient S11 can be below-10dB. The complementary polarization design enables the device to have a multi-polarization coping capability in a wide frequency band. The problem that a traditional fixed-frequency wave absorber is poor in adaptability is solved, and a new technical scheme is provided for radar wave absorption and electromagnetic compatibility application.

The invention discloses a metamaterial absorber design method and system based on a natural language processing and loop prediction network, and belongs to the field of nanometer photonics device design. The method comprises the following steps: acquiring initial sample data containing metamaterial absorber geometric parameters and corresponding optical response, and training a loop prediction network model to establish a function relationship between the two; performing preprocessing, feature mapping and length calibration on the unstructured design demand text through a natural language processing module to generate a structured feature vector; and inputting the feature vectors into a trained model, and outputting geometric parameters through a loop prediction mode (based on residual feedback optimization) so as to complete on-demand design of the metamaterial absorber. The corresponding system comprises a data acquisition and model training module, a natural language processing module, a loop prediction network module and an on-demand design module. According to the method, the design efficiency can be remarkably improved, the design precision and generalization ability are improved, the design threshold is lowered, the computing resource consumption is reduced, and engineering popularization of the metamaterial absorber is facilitated.

The invention provides a double-layer broadband metamaterial wave absorber covering a C-X-Ku wave band. The double-layer broadband metamaterial wave absorber comprises a copper substrate layer, a first filling layer, a first dielectric layer, a first copper resonance layer, a second filling layer, a second dielectric layer and a second copper resonance layer which are sequentially stacked from bottom to top. The first copper resonance layer comprises a copper square resonance ring, and four edges of the first copper resonance layer are respectively provided with two gaps with fixed intervals. A resistor element is loaded at each gap, and eight resistors are periodically and symmetrically distributed along the ring arms. And the second copper resonance layer comprises four copper right-angle resonance units which are arranged in a central symmetry manner. The two orthogonal arms of each unit are respectively provided with a notch, resistors are loaded at the notches, and the eight resistors are symmetrically distributed on the copper right-angle resonance layer. The invention has the characteristics of high absorption efficiency, wide absorption frequency band and low profile; the method has wide application prospects in the fields of electromagnetic modulation, electromagnetic stealth and the like, and is extremely high in practicability.

The application discloses a three-dimensional water-based frequency selective absorber with switchable electromagnetic properties, comprising a plurality of symmetrically designed three-dimensional gradient structure medium square waveguide frequency selective surface unit structures and periodic water-based metamaterial absorber units; the three-dimensional gradient structure medium square waveguide frequency selective surface unit structure has wideband transmission performance with high frequency selectivity; the periodic water-based metamaterial absorber unit is encapsulated around the frequency selective surface unit structure and has super wideband absorption performance; three transmission poles and two transmission zeros are generated in the three-dimensional gradient structure medium square waveguide frequency selective surface unit structure through cascading three metal square rings in an up-down mode, so that a high-frequency-selectivity wideband three-dimensional frequency selective surface is realized; the transmission out-of-band absorption and the conversion of reflection electromagnetic characteristics are realized by controlling the on-off of water in the periodic water-based metamaterial absorber unit. The application expands the transmission bandwidth, has wide absorption frequency band and high absorption rate, and can realize dual polarization.

A selective metamaterial absorber and method for fabricating the same is disclosed. The method includes deposing a first metal layer on a first surface of a substrate and on a plurality of nanowires extending outward from the first surface of the substrate, the plurality of nanowires forming an array on the first surface, the substrate further including a second surface opposite the first surface. The first metal layer may be deposed using conformally sputtering. The substrate and the plurality of nanowires may be composed of silicon, and the first metal layer may be composed of tungsten. The first metal layer may be composed of a material having a penetration depth for a wavelength range of interest. The first metal layer may be at least three times thicker than the penetration depth.

The invention discloses a graphene-based multi-narrow-band metamaterial absorber, and aims to solve the problem that the absorption performance of an existing multi-narrow-band metamaterial absorber cannot meet the actual requirements. In the aspect of structural design, the device adopts a six-layer heterogeneous composite structure which comprises a metal pattern layer, a graphene pattern layer, a first dielectric layer, a metal enhancement layer, a second dielectric layer and a metal bottom layer from top to bottom. The narrow-band absorption behavior from double peaks, three peaks to four peaks is realized in the working frequency range of 0.5-1.3 THz, and the absorption intensity of all absorption peaks is improved to more than 90%. A reliable structural scheme is provided for the design of the high-performance multi-narrow-band metamaterial absorber, the absorption efficiency is remarkably improved, and the high-performance multi-narrow-band metamaterial absorber has important application value in the fields of terahertz communication, radar stealth and the like.

The invention relates to the technical field of electromagnetic wave absorption and metamaterials, in particular to an ultra wide band metamaterial wave absorber based on four-quadrant heterogeneous coupling. The dielectric layer is arranged at the upper end of the metal bottom plate; the metasurface resonance layer is installed at the upper end of the dielectric layer, the metasurface resonance layer is composed of a ceramic substrate and a plurality of resistive films, each resistive film is of a central symmetry structure, the ceramic substrate is arranged at the upper end of the dielectric layer, and the upper end of the ceramic substrate is coated with the resistive films in a silk-screen printing mode; and the protection layer is arranged at the upper end of the metasurface resonance layer, and the design realizes excitation of electromagnetic resonance at adjacent frequency points through resonance structures with different geometrical shapes and sizes, so that coupling and fusion of multiple resonance peaks are formed, and a continuous ultra-wide absorption band is formed in an X-Ku broadband.

In some implementations, a metamaterial absorber (MMA) is configured to absorb a particular range of electromagnetic radiation. The MMA includes a first metal or semiconductor material; a dielectric material disposed on the first metal or semiconductor material; and a second metal material disposed on the dielectric material. A length dimension associated with the MMA is less than or equal to 200 micrometers (μm), a width dimension associated with the MMA is less than or equal to 200 μm, and a thickness dimension associated with the MMA is less than or equal to 8 μm.

The invention discloses a broadband tunable composite metamaterial wave absorber. A wave absorber unit is composed of a 3D printing structure on the upper layer, a PCB structure on the middle layer and a metal floor on the bottom layer. The 3D printing structure is a cuboid frame formed by 3D printing of a PLA material, and the frame is impregnated with carbon paste; metal wire patterns are etched on the upper surface and the lower surface of the PCB structure dielectric substrate, and the metal wire patterns on the upper surface are perpendicular to the metal wire patterns on the lower surface. The metal wire pattern is composed of a bending line of a trunk and parallel branches of branches; the overall structure of the wave absorber is formed by periodically extending units, and the PCB structure and the 3D printing structure are compounded through nylon screws to form the broadband tunable composite metamaterial wave absorber. The invention aims to realize dynamic tuning of wave absorption crest frequencies of P and L wave bands, and realize ultra-wideband wave absorption in S, C, X and Ku wave bands, so that the problem that high-frequency and low-frequency wave absorption of a traditional wave absorber is difficult to be compatible is solved.