74 results about "Metamaterial absorber" patented technology

The invention provides a detector comprising a metamaterial absorber and a micro-bolometer arranged to detect terahertz (THz) radiation. The metamaterial absorber can absorb multiple frequency bands, from the infrared and the THz regions of the electromagnetic spectrum. The detector is scalable to be suitable for use in a focal plane array.

The invention also provides a hybrid of a plasmonic filter, e.g. for optical radiation, and a metamaterial absorber for terahertz (and/or infrared) radiation, to create a single material capable of absorbing narrow band terahertz radiation and filtering radiation in another part of the spectrum, e.g. optical radiation. Such material has great potential in future imaging technology where hybridisation can maximise the spectral information density of an optical system.

The invention provides a tunable metamaterial absorber based on a phase-change material. The phase-change material is induced into a metamaterial based on multilayer structures to enable a working band which absorbs spectra to have a tunability so as to solve the technical problem that the absorber is narrow in spectrum absorption range. According to the tunable metamaterial absorber based on the phase-change material, by means of the characteristic that the dielectric coefficient of the phase-change material changes with the changes of an additional electric field or a temperature, the tunability for the absorber to absorb the spectra is achieved, and the maximum amplitude of accommodation can reach 900 nm.

The invention discloses a low-profile and low-scattering ultra-wideband phased array antenna loaded with a polarization selective wave metamaterial absorber. E-face +/-60-degree scanning and H-face +/-60-degree scanning are realized in a wide band of 6-18GHz, and the cross-section height is only 0.42 of the high frequency (18Ghz) wavelength. The cross polarization of the antenna can be effectivelyimproved through a polarization grating printed on the back surface of a radiation patch unit, and meanwhile, through the loaded polarization selective wave metamaterial absorber, the cross polarization RCS of the antenna is remarkably reduced within the full frequency range of the antenna working frequency without affecting the radiation performance of the antenna, and the absorption effect of the large-angle incident cross polarization electromagnetic wave is good.

The invention relates to a manufacturing method for a broadband THz wave absorber unrelated to wide-angle polarization. The manufacturing method includes that semiconductor silicon with certain doping concentration is selected, a photolithography technique and an ICP (inductively coupled plasma) technique etching or a chemical corrosion technique are adopted on the surface of a silicon wafer to obtain periodically arranged grating layers with reduced reflectivity, and the rest part of the grating layers is a substrate layer with reduced transmissivity. By the arrangement, broadband absorber unrelated to the wide-angle polarization is realized in a THz band. Compared with a conventional metamaterial absorber, the high-doping silicon substrate absorber with the two-dimensional grating structure has the advantages of high absorption frequency band, unrelated to polarization, wide in incident angle and the like; the manufacturing method of the absorber is wide in material taking, simple and efficient, convenient to manufacture and wide in application range; the broadband THz absorber unrelated to the polarization can be manufactured according to actual application scenarios and demands, and absorption rate, absorption frequency band and absorption broadband can be regulated through regulation of structural parameters.

The invention relates to the technical field of metamaterials and terahertz wave application, and provides a single/dual frequency band tunable terahertz wave metamaterial absorber, aiming at solvingthe problem that the frequency band of the existing tunable terahertz wave metamaterial absorber is single and realizing arbitrary switching of the absorption effect of the single frequency band and the dual frequency band. The single/dual frequency band tunable terahertz wave metamaterial absorber includes an upper patterned layer, an intermediate dielectric layer and a lower metal substrate. Theupper patterned layer is formed of a metal-semiconductor silicon resonator periodically tiled and arranged, and the metal-semiconductor silicon resonator comprises a square ring structure and a cross-shaped structure, wherein the four corners of the square ring structure and the top ends of the cross-shaped structure are embedded with semiconductor silicon respectively. The invention can realizearbitrary switching of a perfect absorption effect of dual-frequency band and single-frequency band.

The invention discloses a terahertz microbolometer based on a metamaterial and a preparation method of the terahertz microbolometer. The terahertz microbolometer is composed of two parts including a metamaterial terahertz absorber and a thermal detector, wherein the thermal detector comprises four layers of materials, namely a microbridge supporting layer, a thermistor film, a metal electrode and a passivation layer. The metamaterial terahertz absorber comprises three layers of materials, namely a bottom-layer metal film, an intermediate medium layer and a top-layer metal film. According to the terahertz microbolometer, the metamaterial terahertz absorber and the thermal detector are integrated, heat generated by the metamaterial absorbing terahertz radiation is transmitted to the thermal detector, and then, the electrical property of the thermistor film is changed, so that the terahertz room-temperature detecting and imaging are realized. Due to the adoption of the microbridge structure and the preparation method disclosed by the invention, the problems of microbridge deformation caused by adding the metamaterial and the like are solved, and the microbolometer is high in mechanical stability and terahertz absorptivity. The defect that terahertz waves are difficultly detected by using the traditional microbolometer is overcome; and the terahertz microbolometer is prepared by using the traditional micromachining technology so as to be suitable for industrial production.

The invention provides an intermediate infrared double-frequency-band metamaterial absorber based on a double-L structure and belongs to the field of metamaterials. The absorber comprises a dielectric substrate with double sides covered with metal, wherein the back side of the dielectric substrate is provided with a metal film layer, and the front side of the dielectric substrate is provided with etched double-L metal array patterns consisting of an upper L-shaped pattern and a lower L-shaped pattern. Each L-shaped pattern is formed by connecting a horizontal arm and a vertical arm which are perpendicular to each other, a diagonal line formed by the tail ends of two arms of the upper L-shaped pattern is perpendicular to a diagonal line formed by the tail ends of two arms of the lower L-shaped pattern, and the vertical arms of the L-shaped patterns are arranged on the same line. By reasonably designing the geometric dimension and a lattice period of the L-shaped structure, electromagnetic waves incoming onto the surface of a metamaterial can be completely absorbed. The metamaterial absorber has the advantages of being simple in structure and large in incidence angle, performing absorption through an intermediate infrared band and being provided with two absorption peaks and has wide application prospect in the fields of electromagnetic energy absorption, spectrum detection and the like.

The invention discloses a metamaterial uncooled infrared focal plane multicolor polarization detector and a preparation method thereof. The detector comprises multiple detector pixel units arranged inan array; the pixel unit comprises a substrate structure, a microbridge structure, and a metamaterial absorber structure; the substrate structure comprises a silicon substrate and a first metal electrode layer; the microbridge structure comprises a support layer, a thermo-sensitive layer, a second metal electrode layer and a passivation layer; the metamaterial absorber structure comprises a metalbase layer, a dielectric layer and a metal array layer, and the metal array layer comprises multiple metal arrays arranged in sequence; the four pixel units in two adjacent columns and two adjacent rows are formed into a pixel, the multiple pixel units in each pixel have the same structure, and can be separately formed into one another by rotating. According to the detector and the preparation method thereof provided by the invention, the polarization detection at different bands is achieved by using the strong light absorption at the resonant wavelength caused by the surface plasmon resonance phenomenon in the metamaterial absorber structure and the inherent polarization selection characteristic of the structure.

The invention provides a tunable terahertz graphene metamaterial absorber. The tunable terahertz graphene metamaterial absorber comprises a four-layer structure laminated together: including a patterned graphene metamaterial top layer, a dielectric middle layer, a metal bottom layer and a substrate; the metal bottom layer is arranged on the substrate; the dielectric middle layer is arranged on themetal bottom layer; and the patterned graphene metamaterial top layer is arranged on the dielectric middle layer. Graphene is adopted to replace the conventional metal structure to establish the terahertz metamaterial absorber, and the Fermi energy of two graphene circular plates are tuned through static doping, so that the resonance characteristic of the two graphene circular plates and the nearfield coupling characteristic between the circular plates can be controlled, thereby realizing flexible control on the absorption strength, bandwidth and frequency of the absorber.

The invention discloses an infrared metamaterial absorber. The metamaterial absorber comprises a substrate, a thin film layer, a dielectric layer and a resonance ring structural layer which are arranged in sequence; the resonance ring structural layer comprises at least one metal nanometer ring; the radius of the metal nanometer ring is not greater than 2,000nm; and the width of the metal nanometer ring is not greater than 100nm. The infrared metamaterial absorber can be applied to infrared detection, so that dual-peak or multi-peak absorption of different infrared wavebands can be realized, and the absorptivity can be improved to be 98% or above.

A broadband hyperbolic metamaterial absorber is provided that includes a substrate layer, a plurality of N-doped silicon layers, a plurality of silicon layers, and a silicon grating layer, where the silicon grating layer includes a pattern of through-holes, where the through-holes have a diameter d, a height h, and a periodic separation distance a, where the plurality of N-doped silicon layers and the plurality of silicon layers are arranged in a stack of alternating layers of N-doped silicon layers and silicon layers disposed on the substrate layer, where the silicon grating layer is disposed on the stack of alternating layers of N-doped silicon layers and silicon layers.

The invention belongs to the technical field of microwave antennas and relates to a broadband low-RCS patch antenna based on an FSS transmission and passive reflection cancellation technology. The patch antenna comprises a parasitic patch, an excitation patch, an antenna ground plate, a first dielectric substrate, a second dielectric substrate, an SMA probe joint and a conductor of the SMA probe join which jointly form a patch antenna part; an upper FSS patch, a lower FSS patch and the second dielectric substrate form a double-layer FSS structure part; and a first AMC patch group, a first AMCpatch group and the first dielectric substrate form a mixed AMC surface part. According to the broadband low-RCS patch antenna, two resonances of the double-layer radiation patch can be excited, so that the impedance bandwidth of the patch antenna is broadened; and transmission performance and the wave absorbing performance of a metamaterial absorber can be combined to realize a low RCS characteristic in a broadband range, so that the antenna can be applied to shipborne, airborne and vehicle-mounted military communication systems, and can also be applied to an intelligent skin system to realize stealth and communication functions.

The invention discloses a graphene-metamaterial absorber comprising graphene and a metamaterial absorber body. The metamaterial absorber has an array structure formed by a plurality of single absorbers. Each single absorber includes a bottom layer, an intermediate medium and a top layer; and the bottom layer is made of aluminum, the intermediate medium is made of high-resistance silicon, and the top layer is made of gold. In addition, the invention also includes application of the graphene-metamaterial absorber in antibiotic detection. According to the invention, bottlenecks of complex samplepretreatment process, long analysis period, high organic solvent consumption, higher requirement on professional ability of operators, inconvenience in popularization and use of at the basic level andthe like in the traditional antibiotic detection method are broken through. With the graphene-metamaterial absorber as a carrier, the rapid and nondestructive antibiotic concentration characterization can be realized.

The invention discloses a visible light waveband metamaterial perfect absorber and a self-assembling preparation method thereof, and relates to the technical field of functional optical metamaterials.The metamaterial perfect absorber structurally consists of a gold nano octahedral particle upper layer, a silicon dioxide middle medium layer and a metal aluminum bottom layer, and has a membrane thickness of dozens to hundreds nanometers; and the self-assembling process is carried out between mutually electrified nanoparticles and a metal-medium layer under liquid-phase environment. Through controlling each self-assembling test parameters, the prepared metamaterial absorber is capable of realizing an average absorption rate above 80% in a visible light waveband of 400-760 nm; the metamaterial absorber has two typical nearly-perfect absorption peaks at wavelengths close to 540nm and 727nm; the absorption rate is above 99%; and the metamaterial absorber is non-sensitive to incident light polarization.

The invention relates to the field of electromagnetic metamaterials, in particular to a graphene-vanadium dioxide metamaterial absorber and a tunable terahertz device. The metamaterial absorber is of a multi-layer structure, and according to the structural sequence from top to bottom, the metamaterial absorber comprises a vanadium dioxide resonator array, a continuous graphene layer, a Topas dielectric layer and a metal layer. The vanadium dioxide resonator array comprises a plurality of resonator units which are arranged in an array along the horizontal plane and are made of vanadium dioxide materials, each resonator unit is in an integrated I shape, and an included angle smaller than 90 degrees is formed between each resonator unit and the X-axis direction of the horizontal plane. The continuous graphene layer is formed by arranging single-layer carbon atoms; the vanadium dioxide resonator array is attached to the upper surface of the continuous graphite layer. The Topas dielectric layer is positioned below the continuous graphene layer. The metal layer is located below the Topas dielectric layer. The device overcomes the defects that a traditional metamaterial absorber is poor in tunability, single in function and insufficient in performance index.

The invention discloses a tunable two-band THz absorber based on a Fermi-Dirac material. The tunable two-band THz absorber comprises a lattice unit composed of an absorbing layer 1 and a reflective layer 2 which are closely stacked in the vertical direction. The absorbing layer 1 is a photonic crystal. The reflective layer 2 is a Dirac material. The metamaterial absorber of the present invention is different from a traditional three-layer structure having metal-dielectric-metal configuration. A traditional absorber based on precious metals such as gold, silver, copper and the like can only bedesigned on a fixed absorption peak. If the absorption peak is required to be adjusted to other frequency regions, the geometric parameters of the absorber must be carefully re-optimized. The tunabletwo-band THz absorber not only uses the Dirac material to realize the tunable frequency, but also just uses the photonic crystal so as to be simple in structure, especially free of patterns with metalstructure. Thus, the tunable two-band THz absorber is low in cost and easy to machine.

The invention discloses a sub-wavelength broadband metamaterial absorber for low-frequency noise control. The absorber comprises a plurality of absorber cells. Each sound absorber cell comprises a metamaterial resonator and an acoustic sound absorption sponge thin layer. The metamaterial resonators are integrated with a plurality of Helmholtz resonators. The Helmholtz resonators are fan-shaped. The outer circumferential parts of the fan-shaped resonators are arranged to be labyrinth channels. The circle center parts of the fan-shaped resonators are arranged to be solid bodies, and fan-shaped annular cavities are formed between the labyrinth channels and the solid bodies. The acoustic sound absorption sponge thin layer is coated outside the metamaterial resonator. The absorber can absorb broadband sound energy with the wavelength far larger than the size of the absorber in an approximately perfect mode, and has a good inhibiting effect on broadband low-frequency noise.

The invention discloses a broadband polarization selective metamaterial absorber. The broadband polarization selective metamaterial absorber comprises a substrate, a continuous metal layer, a continuous dielectric layer and stacked gratings in order from bottom to top; the stacked gratings are strip-shaped gratings and are arranged on the surface of the continuous dielectric layer at intervals along the width direction of the stacked gratings; the stacked grating comprises grating metal layers and grating dielectric layers, which are alternately stacked in a height direction, and the gratingmetal layer is located on the outermost layer of the stacked grating; and the widths of the plurality of stacked gratings are different. The broadband polarization selective metamaterial absorber disclosed by the invention is provided with the plurality of stacked gratings with different widths, wherein each stacked grating with a different width corresponds to an absorption peak of electromagnetic waves of different wavelengths, and by setting the sizes of the widths, broadband high absorption is achieved; and in addition, by defining the stacked gratings as the strip-shaped gratings, the broadband polarization selective metamaterial absorber disclosed by the invention realizes the polarization selective absorption of electromagnetic waves. The invention further provides an infrared detector with the above beneficial effects.

The invention relates to the technical field of gas sensors, in particular to an ultra-narrow band infrared thermal radiation light source and a compact infrared gas sensor. The ultra-narrow band infrared thermal radiation light source comprises a first substrate, a supporting layer, a heating plate, a metamaterial absorber and a sealing layer, wherein the metamaterial absorber comprises a metal plate and a microarray structure; the microarray structure is arranged on the metal plate, and the microarray structure comprises a dielectric layer and a metal antenna; and first insulating layers arearranged on the two sides of the heating plate. The compact infrared gas sensor comprises a gas chamber, an infrared emitter and an infrared detector, wherein the infrared emitter uses the ultra-narrow band infrared thermal radiation light source, a reflecting layer is arranged on the inner wall of the gas chamber, and the infrared detector comprises a second substrate, a heat insulation micro-bridge, a heat sensitive layer and a metasurface. The low-radiation compact infrared gas sensor can solve the problems that a traditional infrared gas sensor is large in size, high in cost and the like,and has the advantages of being small in size, low in power consumption, low in cost, capable of detecting various gases at the same time and the like.

The invention relates to a broadband metamaterial absorber compatible with a CMOS (Complementary Metal Oxide Semiconductor) process. The main structure of the metamaterial absorber comprises a lower substrate and an insulating medium which are arranged in sequence. The lower substrate comprises an MIM structure with a visible light waveband and 1550nm optical communication waveband super-absorption function. According to the invention, a broadband metasurface absorption structure compatible with a CMOS process can be realized, and a wide-range high-absorptivity function can be realized in visible light and optical communication wavebands.