143 results about "Fermi level" patented technology

A graphene photodetector of the present invention includes a gate electrode for controlling a Fermi level of graphene, wherein the gate electrode is made of ZnO. By providing the graphene photodetector of the present invention, an ultra-high-speed photodetector having a 3 dB bandwidth exceeding 200 GHz can be realized.

The invention discloses a bifunctional chiral metamaterial surface capable of switching polarization conversion and wave absorption, and belongs to the technical field of electromagnetic metamaterials. The method is used for solving the problem that most existing chiral super-structure surfaces cannot realize dynamic adjustability and quantitative controllability and cannot have dual functions of polarization conversion and wave absorption at the same time. The super-structure surface unit structure is composed of a graphene film layer, a gold-vanadium dioxide resonance layer, a silicon dielectric layer and a bottom-layer continuous gold film. Switching of two functions of polarization conversion and wave absorption is realized by changing the conductivity of vanadium dioxide; polarization conversion and dynamic regulation and control of the wave absorbing efficiency are realized by changing the Fermi level of the graphene; quantitative controllability of polarization conversion and a wave absorbing function is realized by controlling a function weighting function. Besides, the chiral super-structure surface also has the advantages of incident angle robustness, small thickness and small size, has double functions of broadband, and has potential application value in the fields of optical devices, communication equipment, biomedical sensors and the like.

The invention discloses a method for characterizing physical properties of a single-layer graphene / semiconductor heterojunction. The method comprises the following steps: providing a physical property model about a single-layer graphene-semiconductor heterojunction, wherein influence factors comprise the change of Fermi level of single-layer graphene after the heterojunction is formed and the influence of an interface state on a formation position of a contact potential difference; extracting heterojunction electrical characteristics by using a Kelvin probe force microscope; the interface layer spacing is obtained; and importing the heterojunction electrical characteristics and the interface interlayer spacing into a physical characteristic model, and analyzing to obtain physical characteristics. According to the new theoretical model and the method for realizing the nondestructive characterization of the physical characteristics of the heterojunction by using the Kelvin probe microscope based on the theoretical model, the influence of the change of the Fermi level of the single-layer graphene and the interface state on the formation position of the contact potential difference is fully considered; key interface physical properties, especially built-in potential and depletion region characteristics which are crucial to device performance, can be accurately analyzed.

The invention discloses a ferroelectric transistor capable of generating thousands of polarization states and a preparation and use method thereof, the ferroelectric transistor is prepared based on a Gr / hBN heterojunction, the top layer of the heterojunction is a Gr sheet, the bottom layer of the heterojunction is an hBN sheet, the rotation angle between Gr and hBN is controlled within 1 degree through dry transfer, and the Gr / hBN heterojunction is fixed on a silicon wafer substrate (SiO2 / Si); and further depositing a source electrode and a drain electrode through electron beam exposure and electron beam evaporation processes to construct the Gr / hBN ferroelectric transistor. A single device can generate dozens of discrete polarization states through source-drain pulse modulation; meanwhile, the Fermi level of the graphene can be reversibly adjusted among dozens of nonvolatile doping levels by overlapping the grid voltage while the source-drain pulse acts, and the polarization state can be modulated through the source-drain pulse at each doping level; the number of stable polarization states reaches thousands at room temperature; different polarization states may be retained for more than 105 seconds, and may be maintained for more than 10 years according to linear extrapolation.

The invention provides a method and device for calculating the electron spinning state of an iron-based biphase composite magnetic material, and relates to the technical field of magnetic materials. The method comprises the following steps: establishing a heterojunction model of a biphase composite magnetic material; according to the method, generalized gradient approximation in a density functional theory is adopted as an exchange-correlation functional, relaxation is carried out on atomic positions in a heterojunction model, so that the total energy of a system is the lowest, and geometric structure optimization is carried out on the heterojunction model; performing spin polarization calculation on the optimized heterojunction model to obtain spin upward state densities and spin downward state densities of different atoms in the heterojunction model, and analyzing electronic state distribution near a Fermi level; and quantitatively evaluating the magnetic characteristics of the heterojunction model according to the spin upward state density and the spin downward state density of each atom. According to the method, an interface magnetic coupling mechanism can be disclosed, and a theoretical basis can be provided for development of a high-performance magnetically controlled reactor iron core material.

The invention belongs to the field of new energy and relates to a novel electric energy acquisition technology. The non-equilibrium conductors are substances with the same Fermi level, and the contact potential generated by the non-equilibrium field effect existing between the non-equilibrium conductors with different mass and form is converted into electric energy for utilization. A medium (hereinafter referred to as an electric conduction control medium) which has electric conduction performance and controls voltage and limits electric conductivity under a certain condition is placed between conductors, good close contact is achieved between the medium and the conductors, and the result is that under the effect of the electric conduction control medium, non-equilibrium field contact potential is converted into electric energy capable of being continuously output.

The invention belongs to the technical field of sodium ion batteries, and particularly relates to a high-entropy sodium ion P2 type positive electrode material as well as a preparation method and application thereof. Compared with the prior art, the high-entropy sodium ion P2 type positive electrode material provided by the invention at least contains three doping elements, and when the ion radius of the doping element is close to the ion radius in the material body structure and the Fermi energy levels are different, the charge order of the transition metal layer can be eliminated; meanwhile, after doping, the proportion of Ni < 3 + > and Mn < 3 + > is reduced, and the Jahn-Teller effect of the material can be improved; in addition, the doped elements can improve ordered arrangement of Na < + > / vacancies, improve the diffusion rate of Na < + > and reduce migration activation energy; moreover, the doped elements can inhibit phase change, reduce interlayer spacing and material volume change, and enhance structural stability.

The invention relates to the technical field of semiconductor materials, and discloses a Si-doped epsilon-Ga2O3 material with high conductivity and deep ultraviolet light absorption performance and a preparation method, the doping concentration of Si in the Si-doped epsilon-Ga2O3 material is 0.83 at%-2.5 at%, and Si atoms replace tetrahedral coordinated Ga (1) atoms in epsilon-Ga2O3. By accurately controlling the Si doping concentration to be 0.83-2.5 at% and enabling Si atoms to replace tetrahedral coordinated Ga (1) atoms in epsilon-Ga2O3, the electronic structure of the material is effectively improved, the Fermi level moves upwards to enter a conduction band after Si doping, and Si3s orbital electrons occupy the conduction band bottom (CBM), so that the carrier concentration is increased, the effective mass of the electrons is reduced, and the conductivity of the material is remarkably improved; tests show that compared with an intrinsic epsilon-Ga2O3 material, the conductivity of the doped material is improved by 1-3 orders of magnitude, strict requirements of high-power electronic components and the like on the conductivity of the material are met, heat loss of the electronic components due to resistance is reduced, and the working efficiency and stability of the components are improved.

The invention discloses an adjustable non-reciprocal wave absorber based on a graphene-Weel semimetal plasmon structure, and relates to the field of nano photonics, and the wave absorber comprises a graphene film with a certain thickness; the polymer dielectric layer is laid at the lower part of the graphene film; the germanium grating layer is arranged at the lower part of the polymer dielectric layer; the Weel semimetal layer is arranged at the lower part of the germanium grating layer; the zinc selenide dielectric layer is arranged at the lower part of the Weel semimetal layer; and the silver substrate is arranged at the bottom of the Weel semimetal layer. According to the adjustable non-reciprocal wave absorber, dynamic regulation and control of the non-reciprocal absorption coefficient can be improved by properly adjusting the Fermi level and the incident light angle of the graphene, then switching between the non-reciprocal state and the reciprocal state of a device is achieved, and the effect of enhancing the practicability of the non-reciprocal device is achieved.

The invention discloses a material classification method and device based on an ultraviolet electron spectrum, a medium and a product, and relates to the technical field of material surface science and data analysis. The method comprises the following steps: acquiring ultraviolet light electron energy spectrum data of a target material to be analyzed, and extracting a first spectrum curve from the energy spectrum data; obtaining a conductor characteristic identification result of the target material according to the first spectrum curve; under the condition of determining that the target material does not have the conductor characteristics based on the conductor characteristic identification result, extracting a second spectrum curve in a preset valence band top energy interval extending towards the negative energy direction by taking the Fermi level as a starting point from the ultraviolet light electron spectrum data, and performing multi-dimensional characteristic fusion on the second spectrum curve, generating a semiconductor characteristic identification result of the target material based on the fusion result; and determining a classification result of the target material according to the semiconductor characteristic identification result. According to the scheme, the conductive attributes of the target material can be quickly and accurately classified.

The present invention provides a surge protection element that can smoothly handle an unnecessary current produced by a harmful pulse. A surge protection element 10 is the surge protection element 10 including a first electrode 11, an n-type semiconductor layer 12, a second electrode 13 sequentially joined in a designated direction. A portion at least from any position in the n-type semiconductor layer 12 toward the second electrode 13 in the designated direction is composed of a graded composition layer 12B, whereby in a state in which a voltage is not applied, a bandgap Eg of the portion gradually increases in the designated direction, and part of a conduction level Ec exceeding a Fermi level Ef in the portion gradually increases in the designated direction.

The invention discloses a method for regulating and controlling the spin state of a two-dimensional antiferromagnetic semiconductor by using a JANUS structure, and the method comprises the following steps: constructing a two-dimensional antiferromagnetic semiconductor material structure model, and carrying out the geometric optimization; calculating magnetic properties and electronic properties based on the optimized structure; replacing halogen atoms on one side to obtain a two-dimensional A-type antiferromagnetic semiconductor material structure model with a JANUS structure, and performing geometric optimization; based on the optimized JANUS structure, the magnetic property and the electronic property of the JANUS structure are calculated; and comparing the spin state near the Fermi level of the optimized two-dimensional antiferromagnetic semiconductor material with the spin state near the Fermi level of the optimized two-dimensional A-type antiferromagnetic semiconductor material with the JANUS structure. According to the method, on the basis of a two-dimensional antiferromagnetic material, a JANUS structure is introduced, the magnetism of the material is not changed, meanwhile, a single polarization spin electron current is introduced at the Fermi level, and a theoretical model is provided for preparing related materials.

The invention discloses a defect layer modified TiO2 nanowire array photo-anode and a preparation method thereof, and belongs to the technical field of photoelectrochemistry. The Ti thin film is deposited on the surface of TiO2 NWAs growing on the substrate in a magnetron sputtering mode, then annealing treatment is conducted in the N2 atmosphere, Ti can capture O atoms in TiO2 crystal lattices in the annealing process, a TiO2 defect layer containing oxygen vacancies is formed on the surface, the lower Fermi energy level is helped to be obtained, the Fermi energy level tends to be balanced when the Ti thin film and a main body TiO2 nanowire form a homojunction, and therefore the TiO2 defect layer with the oxygen vacancies is formed. Therefore, a built-in electric field is generated, migration of photon-generated carriers is promoted, and the utilization rate of light is enhanced. The surface defect state concentration is regulated and controlled by further regulating and controlling conditions such as Ti film deposition time and annealing temperature, so that the prepared photo-anode has better PEC performance; the invention provides an effective means for regulating and controlling the photoelectrocatalytic performance of TiO2, and also provides a theoretical basis for related applications.

Provided is a sensor device having high measurement sensitivity for measuring an external electric field. The sensor device can measure the electric field intensity of the external electric field. The sensor device includes: a first dielectric layer; a channel layer disposed directly on the first dielectric layer, having a channel region, having an atomic layer material film of one or more atomic layers formed of a two-dimensional transition metal disulfide; and a first electrode and a second electrode which are in electrical contact with the channel layer and are disposed so as to face each other with the channel region therebetween, the channel layer having a first surface and a second surface, the first surface being disposed on the first dielectric layer, the second surface being exposed to the outside, or the second dielectric layer being disposed on the second surface. A Fermi level of the channel layer is in a conduction band or valence band of the channel layer and in a trap level band in the first dielectric layer that interfaces with the channel layer.

This application relates to a P-type gallium oxide and a preparation method thereof. The preparation method of the P-type gallium oxide includes providing a substrate, the material of the substrate includes β-gallium oxide, and a co-doping of shallow-level acceptor impurities and deep-level acceptor impurities is formed on the substrate. Among them, the shallow-level acceptor impurities are elements of the same group as oxygen. When the deep-level acceptor impurities and the shallow-level acceptor impurities are co-doped, the deep-level acceptors of the deep-level acceptor impurities can combine with the acceptor levels of the shallow-level acceptor impurities, further pushing the Fermi level towards the valence band top. This combined effect significantly improves the stability of P-type conductivity of β-gallium oxide.

The invention relates to the technical scheme. The invention belongs to the field of new energy and nuclear energy battery technology. The method is a comprehensive and systematic method for directly converting radioactive substances and radiation of the radioactive substances into electric energy. The utilization of radioactive substances is the utilization of a contact potential effect existing among substances with different Fermi levels. The utilization of the radiation is the utilization of the contact potential effect of a non-Fermi level; according to the technical scheme, the contact potential effect formed by the electric potential generated by radiation rays and radiation on a polar plate is utilized, and the effect is converted into electric energy capable of being actually utilized under the action of a medium which has conductivity and controls voltage and limits conductivity under a certain condition.

The application relates to the fields of material preparation technology and radio frequency devices, in particular to a thin film substrate structure and an acoustic filter. The thin film substrate structure comprises a supporting substrate, an interface layer, an insulating layer and a functional layer; the supporting substrate has opposite first and second surfaces, and the interface layer is located on the second surface; the insulating layer is located on the side surface of the interface layer away from the supporting substrate; the functional layer is located on the side surface of the insulating layer away from the supporting substrate; and the interface layer has at least one of a deep energy level defect and a preset band gap width. The application plays a pinning effect on the Fermi level of the device by the interface layer having at least one of a deep energy level defect and a preset band gap width. The surface local conductance effect of the supporting substrate when working at a high frequency is effectively inhibited, the generation of high-order harmonics is inhibited, and the linearity of the device is optimized.

The invention relates to the technical field of photocatalysis, in particular to an I-type p-n heterojunction photocatalyst as well as a preparation method and application thereof. According to the photocatalyst, an n-type semiconductor metal organic framework NUS-8 is used as a matrix, a p-type semiconductor CuO is loaded, and an I-type p-n heterojunction structure is constructed. The preparation method comprises the following steps: by taking NUS-8 and cupric salt as raw materials and N, N-dimethylformamide as a dispersion medium, performing coordination anchoring on Cu < 2 + > on the surface of NUS-8 under solvothermal, oxidizing to form CuO nanoparticles, and constructing a coupling interface to obtain the photocatalyst. An energy band of the material is in I-type (straddling type) arrangement, a built-in electric field is formed by Fermi level difference at an interface, directional separation and migration of photo-induced electrons and holes are effectively driven, and the catalytic activity and stability of a photocatalytic reaction are remarkably improved. The material has the advantages of simple and convenient process, stable structure, excellent photocatalytic performance and the like, and is suitable for environment and energy related fields such as photocatalytic CO2 reduction and the like.

The present invention provides a quantum device and a method for manufacturing the same that enable the injection of Cooper pairs into the edges of a two-dimensional topological insulator without the use of heterointerfaces, and the control of the Fermi level at the edges of the two-dimensional topological insulator. [Solution] The quantum device comprises a monolayer 4 of tungsten ditelluride having a 1T' type crystal structure, a first electrode 6a that provides a first potential to a first portion of the monolayer that is a part of the monolayer and separated from the outer periphery of the monolayer, and a second electrode 6b that provides a second potential to a second portion of the monolayer that is a part of the monolayer and includes a certain range of the outer periphery of the monolayer. The first electrode is positioned so that Cooper pairs generated by the application of the first potential to the first portion can penetrate a third portion that is a part of the second portion and includes the certain range. The third portion is a region in which topological superconductivity occurs when Cooper pairs penetrate.

The invention discloses a fine simulation method of a CdTe-based II-VI group compound thin film solar cell and a cell structure designed based on the method. According to the method, a physical model of a CdTe-based battery is established through numerical simulation, then the energy band structure of a carrier transport layer is systematically optimized, and the quantitative criteria that a hole transport layer needs to meet the requirements that the Fermi energy level is lower than that of an absorption layer and the hole transport layer has enough positive conduction band offset and an electron transport layer needs to have a wide band gap and moderate positive conduction band offset are determined. And for the optical layer, the optimal thickness of the antireflection layer is determined, the enhancement effect of the optical path gain of the textured structure on optical absorption is quantified, and the maximization of the light capture efficiency is realized. According to the method, through electrical-optical coupling simulation, the CdTe-based solar cell structure of which the conversion efficiency is remarkably improved can be accurately predicted and guided to be designed, the defects that a traditional experiment is high in trial and error cost and long in period are effectively overcome, and a reliable theoretical design and optimization tool is provided for research and development of a high-efficiency and low-cost CdTe-based solar cell.

The present invention discloses an ultra-narrowband absorber tunable from visible to mid-infrared, and its structure includes a substrate, a bottom Bragg reflector, a resonant cavity layer, a lower electrode, a dielectric spacer layer, an upper electrode, a bilayer graphene structure capable of mutual electrostatic gating, and a top Bragg reflector. The absorber is based on Fabry-Perot cavity resonance to form a resonance mode within the resonant cavity layer between the bottom and top Bragg reflectors. The radiation loss rate of this resonance mode is mainly determined by the constituent components, the number of periods of the Bragg reflector, and the Fermi level of graphene together, while the absorption loss rate is determined by the Fermi level of graphene. The bandwidth of the resonance mode is jointly determined by the magnitudes of the radiation loss rate and the absorption loss rate. By constructing a Bragg reflector with appropriate components and number of periods and regulating the Fermi level of graphene to make the system reach critical coupling, an ultra-narrowband perfect absorption tunable from visible to mid-infrared can be achieved.

The invention provides an n-type Mg3Bi2-based composite thermoelectric material as well as a preparation method and application thereof, the chemical composition of the n-type Mg3Bi2-based composite thermoelectric material is Mg 3.2 (Bi 0.7 Sb 0.3) 1.99 Te 0.01-Q2Se x wt%, Q is Cu and / or Ag element, and the sum of x wt% and x wt% is 100%. X is 0.0 lt; and x is less than or equal to 1.5. The invention also discloses a preparation method and application of the n-type Mg3Bi2-based composite thermoelectric material. The Fermi level of the n-type Mg3Bi2-based composite thermoelectric material goes deep into a conduction band, the electrical property is excellent, and the power factor is kept at a high level; the total thermal conductivity is reduced, so that the thermoelectric figure of merit of the n-type Mg3Bi2-based thermoelectric material is remarkably improved, and the n-type Mg3Bi2-based thermoelectric material has a wide application prospect in the field of semiconductor thermoelectric materials.

This invention discloses a ferroelectric transistor capable of generating thousands of polarization states and its fabrication and application method. The ferroelectric transistor is fabricated based on a Gr / hBN heterojunction, with a Gr sheet as the top layer and an hBN sheet as the bottom layer. The rotation angle between Gr and hBN is controlled within 1° using a dry transfer method. The Gr / hBN heterojunction is fixed on a silicon substrate (SiO2 / Si). Source and drain electrodes are further deposited using electron beam lithography and electron beam evaporation processes to construct the Gr / hBN ferroelectric transistor. A single device can generate dozens of discrete polarization states through source-drain pulse modulation. Simultaneously, by superimposing a gate voltage while applying source-drain pulses, the Fermi level of graphene can be reversibly tuned between dozens of non-volatile doping levels, and the polarization state can be modulated by source-drain pulses at each doping level. The number of stable polarization states reaches thousands at room temperature; different polarization states can be retained for more than 10^6 times. 5 Seconds, and based on linear extrapolation, it could last for more than 10 years.

A method for forming a semiconductor structure, comprising: providing a substrate, including a substrate and a fin standing on the substrate, along the extension direction of the fin, the fin includes a channel region, the channel region is used to form a stacked work function layer; forming a gate dielectric layer conformally covering the top and sidewall of the fin in the channel region; forming a first work function layer conformally covering the gate dielectric layer in the channel region; forming a filling layer on the first work function layer between adjacent fins, the filling layer exposes at least the first work function layer on the top of the fin, the Fermi level of the material of the filling layer is closer to the Fermi level of the fin than the Fermi level of the material of the stacked work function layer; forming a second work function layer covering the first work function layer and the filling layer, the second work function layer and the first work function layer are used to constitute the stacked work function layer. The second work function layer is located on the top of the first work function layer and the filling layer, which reduces the probability of generating void defects in the second work function layer and improves the uniformity of the threshold voltage of the device.

The embodiment of the present application discloses a kind of transmission type terahertz absorption structure and preparation method thereof.Transmission type terahertz absorption structure includes at least one transmission type terahertz absorption composite film layer, transmission type terahertz absorption composite film layer includes substrate and the metal grating layer, insulating layer and graphene layer that are sequentially stacked in substrate side;Wherein metal grating layer and graphene layer are electrically connected with external power supply.The technical scheme of the embodiment of the present application is based on electromagnetic wave theory and the electrical properties of graphene, by additional voltage control Fermi level of graphene, adjust the absorption of absorption structure to terahertz, make the terahertz wave that pass through the present absorption structure have different intensity information under the influence of external voltage, play the role of switch, and have the advantages of active regulation, real-time control, accurate control, suitable for terahertz spectrum imaging analysis, single-pixel imaging and spectrum measurement etc.

The gallium nitride semiconductor purple light laser comprises a substrate, a lower coating layer, a lower waveguide layer, an active layer, an upper waveguide layer and an upper coating layer which are sequentially arranged from bottom to top. According to the gallium nitride semiconductor purple light laser, the distribution characteristic of the drift rate of saturated electrons in the lower waveguide layer of the gallium nitride semiconductor purple light laser is specifically designed, so that the lower waveguide layer forms a carrier pinning lower waveguide layer, redundant carriers are limited in an active region under the condition of large injection, electron leakage current is eliminated, the carrier transport and injection efficiency is improved, and the quantum efficiency is improved. The bipolar conductance effect and the junction voltage saturation at the threshold are inhibited, and the series resistance and voltage are reduced; meanwhile, an acceleration hole and an electronic quasi-Fermi level are pinned, and the rate of stimulated radiation exceeding spontaneous radiation is accelerated, so that carriers are completely converted into photons to be output, symmetry breaking corresponding to a far-equilibrium state is inhibited, a deep level trap of a lower waveguide layer is reduced, and the capture effect of a depletion region is enhanced. And the problems of junction voltage jump and series resistor sinking are solved.

A semiconductor device includes a semiconductor region made of a material to which conductive impurities are added, an insulating film formed on a surface of the semiconductor region, and an electroconductive gate electrode formed on the insulating film. The gate electrode is made of a material whose Fermi level is closer to a Fermi level of the semiconductor region than a Fermi level of Si in at least a portion contiguous to the insulating film.

The invention discloses a method for exploring intrinsic defects of a semi-Heusler alloy, and relates to the field of thermoelectric materials.The method comprises the steps that firstly, defects are introduced into a compound, then theoretical calculation is conducted through a first principle method, and main intrinsic defects are determined by analyzing the relation between formation energy and Fermi energy level of the defects; theoretical analysis of the defect concentration, the electronic structure, the relation between the defect and the chemical bond and other properties is carried out on the basis, a theoretical guidance direction for achieving performance optimization through a means of reasonably controlling system defects is provided for thermoelectric materials, and a new understanding is provided for thermoelectric performance optimization.

The invention discloses a terahertz detector based on a Dirac semimetal nanowire structure, and particularly relates to the terahertz field, the terahertz detector comprises a gold reflecting layer, a dielectric layer and a Dirac semimetal material layer, the dielectric layer is arranged on the top of the gold reflecting layer, and the Dirac semimetal material layer is arranged on the top of the dielectric layer; and the Dirac semi-metal material layer is a Dirac semi-metal nanowire array layer. A Dirac semimetal-silicon dioxide-gold three-layer structure is adopted, Fano resonance and F-P resonance are excited to be coupled through a nanowire array, high absorption (99.02% at most) of seven frequency bands within the range of 0-14.5 THz is achieved, dynamic tuning is achieved by adjusting the Fermi level of Dirac semimetal, the sensitivity reaches 5421.43 GHz / RIU, the quality factor is 35.204 (1 / RIU), and the device is stable in structure, easy to process and suitable for large-scale production. The device is suitable for the fields of terahertz detection, imaging, biosensing and the like.

The invention discloses an adjustable ultra-wideband terahertz metamaterial wave absorber, and belongs to the technical field of terahertz wave absorbers. The wave absorber is composed of a plurality of same metamaterial structure units which are periodically arranged, and each metamaterial structure unit is made of three layers of composite materials, wherein the first layer is a graphene pattern layer, the second layer is a polyimide dielectric layer, and the third layer is a copper reflecting layer. Wherein the graphene pattern layer adopts a combined design of four groups of square and L-shaped structures, and the four groups of structures form a biaxial symmetry layout through geometric coupling. The structure has the characteristics of wide absorption bandwidth, high absorption rate and dynamic adjustability, can realize more than 90% of efficient absorption in the frequency band of 2.28-4.68 THz, and can adjust the Fermi level of the graphene by externally applying bias voltage to realize rapid switching between the absorption state and the reflection state. The device is suitable for various application scenes such as terahertz communication, sensing and stealth.