阅读说明：本技术 一种双带可灵活选择性调控的石墨烯-金属槽超材料太赫兹慢光器件 (A kind of graphene-metallic channel Meta Materials Terahertz slower rays device of biobelt flexible choice regulation ) 是由 贺训军 王越 田玲 杨文龙 杨玉强 姜久兴 于 2019-09-04 设计创作，主要内容包括：一种双带可灵活选择性调控的石墨烯-金属槽超材料太赫兹慢光器件,涉及电磁与电磁波技术领域。本发明的目的是要解决现有的可调谐太赫兹EIT超材料慢光器件单工作频带,可调谐范围窄、结构和制备工艺复杂、激励方式所需外部设备繁琐、功能单一、可靠性低、活性材料可选范围窄以及线性属性小的问题。硅衬底层上设置有二氧化硅绝缘层,二氧化硅绝缘层上设置有周期性排列的图形化两石墨烯带结构,石墨烯带结构上设置有周期性排列的图形化金属槽结构,两石墨烯结构分别与第一金属电极Pad 1和第二金属电极Pad 2连接。本发明可获得一种双带可灵活选择性调控的石墨烯-金属槽超材料太赫兹慢光器件。(A kind of graphene-metallic channel Meta Materials Terahertz slower rays device of biobelt flexible choice regulation, is related to electromagnetism and electromagnetic wave technology field.The invention aims to solve existing tunable Terahertz EIT Meta Materials slower rays device list working band, tunable range is narrow, structure and preparation process are complicated, external equipment is cumbersome, has a single function, the problem that reliability is low, the optional narrow range of active material and linear properties are small needed for energisation mode.Silicon dioxide insulating layer is provided in silicon substrate layer, the graphical two graphene ribbons structure of periodic arrangement is provided on silicon dioxide insulating layer, the patterned metal slot structure of periodic arrangement is provided in graphene ribbon structure, two graphene-structureds are connect with the first metal electrode Pad 1 and the second metal electrode Pad 2 respectively.The present invention can get a kind of graphene-metallic channel Meta Materials Terahertz slower rays device of biobelt flexible choice regulation.)

1. a kind of graphene-metallic channel Meta Materials Terahertz slower rays device of biobelt flexible choice regulation, it is characterised in that It includes Terahertz slower rays device function structure, silicon dioxide insulating layer (2), silicon substrate (1) and gate electrode structure；

The Terahertz slower rays device function structure is made of the metamaterial structure unit of periodic arrangement, the metamaterial structure Unit is made of patterned metal slot structure (4) and graphical two graphene ribbons structure (3), graphical two graphene ribbons structure (3) patterned metal slot structure (4) are set on；The gate electrode structure is by the first metal electrode Pad1 (5) and the second metal electricity Pole Pad2 (6) is formed, and is provided with silicon dioxide insulating layer (2) on the silicon substrate (1), silicon dioxide insulating layer is set on (2) It is equipped with graphical two graphene ribbons structure (3), the graphical two graphene ribbons structure (3) is periodic arrangement；First metal Electrode Pad1 (5) and the second metal electrode Pad2 (6) is separately positioned on the two sides of the Terahertz slower rays device upper surface, period Property arrangement graphical two graphene ribbons structure (3) respectively with the first metal electrode Pad1 (5) and the second metal electrode Pad2 (6) Connection；

Left side graphite in the first metal electrode Pad1 (5) to second metal electrode Pad2 (6) direction, Terahertz slower rays device Alkene strip is to be interconnected by the first graphene ribbon structure (3-1), and the first electricity of formation is connect with the first metal electrode Pad1 (5) Pole；The corresponding right side along the second metal electrode Pad2 (6) to first metal electrode Pad1 (5) direction, Terahertz slower rays device Graphene strip is to be interconnected by the second graphene ribbon structure (3-2), and connect with the second metal electrode Pad2 (6) formation the Two electrodes；Wherein the metal wire of connection left side graphene strip and the metal wire of connection right side graphene strip are not attached to, and first Electrode and second electrode difference；

The patterned metal slot structure (4) is made of two pairs of horizontally disposed metallic channels and a metallic channel being vertically arranged, The two sides for the metallic channel being vertically arranged are arranged in two pairs of horizontally disposed metallic channels, along the metamaterial structural unit central Line, two pairs of horizontally disposed metallic channel horizontal directions are symmetrical, and vertical direction is asymmetric；The metallic channel being vertically arranged has one Run through the vertical gap of metamaterial structure unit along groove center line；The size of the graphical two graphene ribbons structure (3) is length It spends identical and of different size, is vertically disposed on two pairs of horizontally disposed metallic channels in the following, along the metamaterial structure unit Center line, vertically disposed graphical two graphene ribbons structure (3) horizontal direction is symmetrical, and vertical direction is asymmetric；Metal is super There is a vertical gap between material structure adjacent cells.

2. a kind of graphene-metallic channel Meta Materials Terahertz of biobelt flexible choice regulation according to claim 1 Slower rays device, it is characterised in that the material of the silicon substrate (1) is low-doped High Resistivity Si, the patterned metal slot structure (4) material is Al, Cu or Au, with a thickness of 0.2 μm.

3. a kind of graphene-metallic channel Meta Materials Terahertz of biobelt flexible choice regulation according to claim 1 Slower rays device, it is characterised in that the on-load voltage V between first electrode Pad1 and second electrode Pad2 and silicon substrate (1)₁And V₂, On-load voltage V₁And V₂Can it is electrostatically-doped regulation graphene Fermi can, by control two electrode voltage sizes can flexibly tune two Fermi's energy of side graphene strip, adjusts the stiffness of coupling of each element；By changing the stiffness of coupling of three interelements, can flexibly adjust Control the amplitude of Terahertz slower rays device electromagnetically induced transparent window.

4. a kind of graphene-metallic channel Meta Materials Terahertz of biobelt flexible choice regulation according to claim 1 Slower rays device, it is characterised in that the metamaterial structure unit is the direction x element length P_xIt is 300 μm, the direction y element length P_y It is 160 μm, 2 μm of gap is arranged in metamaterial structure unit two sides, and 2 μm of seam is arranged in the metamaterial structural unit central Gap.

5. a kind of graphene-metallic channel Meta Materials Terahertz slower rays device preparation method of biobelt flexible choice regulation, It is characterized in that the preparation method is completed according to the following steps:

One, liner oxidation: silicon dioxide insulating layer (2) are grown on low-doped HR-Si substrate (1) using oxidation technology, are obtained There is the silicon substrate (1) of silicon dioxide insulating layer (2) to growth；

Two, CVD method prepares graphene: first copper foil substrate is pre-processed with ferric nitrate, then using methane as carbon source, argon gas and For hydrogen respectively as protection and reducing gas, copper foil substrate after the pre-treatment carries out heat treatment growth graphene, obtains stand-by Graphene；

Three, graphene substrate shifts: then spin coating is had the graphene of PMMA to be placed in iron chloride by spin coating PMMA on the surface of graphene Corrode copper foil substrate in solution, the graphene after obtaining corrosion copper foil, then in deionized water by the graphene after corrosion copper foil It is cleaned multiple times, the graphene after being cleaned, finally has the silicon substrate (1) of silicon dioxide insulating layer (2) from going with growth Graphene is fished in ionized water, and removes the PMMA on graphene and secondary cleaning processing, is completed the graphite in copper substrate Alkene, which is transferred to growth, to be had on the silicon substrate (1) of silicon dioxide insulating layer (2)；

Four, graphene is graphical: having the silicon substrate of silicon dioxide insulating layer (2) (1) being transferred to growth using mechanical spin-coating method On graphene surface spin coating photoresist, then there is the graphene of photoresist to dry spin coating, be successively exposed, develop And fixing, the graphical photoresist exposure mask of preparation graphene ribbon structure is obtained, then using oxygen plasma to the stone of photoresist exposure mask Black alkene performs etching, and finally removes photoresist using acetone soak and cleans, obtains patterned graphene band structure；

Five, metal patternization: mechanical spin-coating method spin coating photoetching is first used in the patterned graphene body structure surface that step 4 obtains Glue is successively exposed, develops and is fixed, and obtains the graphical photoresist exposure mask for preparing patterned metal slot structure (4), then Metal is deposited on the graphical photoresist exposure mask for preparing patterned metal slot structure (4) using magnetron sputtering method, is finally set again 24 hours stripping metals and removal photoresist are impregnated in acetone soln, obtain patterned metal slot structure (4) and gate electrode knot Structure completes a kind of graphene-metallic channel Meta Materials Terahertz slower rays device preparation of biobelt flexible choice regulation.

6. a kind of graphene-metallic channel Meta Materials Terahertz of biobelt flexible choice regulation according to claim 5 The preparation method of slower rays device, it is characterised in that oxidation technology described in step 1 is dry oxidation technique, the dry method oxygen Chemical industry skill is that at high temperature, silicon and oxygen reaction generate silica.

7. a kind of graphene-metallic channel Meta Materials Terahertz of biobelt flexible choice regulation according to claim 5 The preparation method of slower rays device, it is characterised in that heat treatment described in step 2 is, extremely by pretreated copper foil silicon 1050 DEG C, 1000 DEG C are then cooled the temperature to, is further continued for being cooled to room temperature.

8. a kind of graphene-metallic channel Meta Materials Terahertz of biobelt flexible choice regulation according to claim 5 The preparation method of slower rays device, it is characterised in that cleaning described in step 3 is to have the graphene of copper foil to be placed in corrosion Graphene in ionized water, after being cleaned multiple times, after being cleaned；Substrate transfer and secondary cleaning processing in step 3 are to use Growth has the silicon substrate (1) of silicon dioxide insulating layer (2) to fish for the graphene after cleaning from the bottom of deionized water, finally will fishing Graphene after the cleaning taken, which is placed in acetone, impregnates removal PMMA, and is cleaned multiple times with deionized water, completes copper substrate On graphene be transferred on silicon dioxide insulating layer (2).

9. a kind of graphene-metallic channel Meta Materials Terahertz of biobelt flexible choice regulation according to claim 5 The preparation method of slower rays device, it is characterised in that the step of mechanical spin-coating method described in step 4 is；First turned with 500r/min Fast spin coating 20s, then with the revolving speed spin coating 60s of 4000r/min, then with the revolving speed spin coating 20s of 500r/min.

10. a kind of graphene-metallic channel Meta Materials Terahertz of biobelt flexible choice regulation according to claim 5 The preparation method of slower rays device, it is characterised in that metal is deposited using magnetron sputtering method described in step 5, the metal is Al, Cu or Au, with a thickness of 0.2 μm.

Technical field

The present invention relates to Electromagnetic Fields & Magnetic Waves technical fields, and in particular to a kind of graphene-metallic channel Meta Materials are too Hertz slower rays device.

Background technique

Electromagnetically induced transparent (Electromagnetically Induced Transparency, EIT) is a kind of utilization Quantum coherence effect eliminates a kind of technology of medium influence during Electromagnetic Wave Propagation.It refers to the electricity by the way that a beam intensity is added In the case where magnetic radiation (referred to as coupling light), the dim light for keeping the coupling frequency between two energy levels of a branch of frequency and atom close, In The technology that the absorbing phenomenon that should be generated when passing through medium disappears.Initial EIT phenomenon is found in three-lever system, wherein | 1 > be ground state, | 2 > and | 3 > are excitation state, and when detection light a branch of to medium emission, atom will be from ground state | 1 > be energized into it is sharp Send out state | 3 >, transition occurs.Since light is absorbed, the intensity for receiving detection light will weaken significantly even to disappear.It is a branch of when being added With excitation state | 2 > and | 3 > frequency it is similar when coupling light, make that strong coupling occurs between two energy levels, so that making to excite State | 3 > energy level cleave, form energy state, referred to as dressed state similar in two energy.At this point, having when detection light incidence identical Probability to the two dressed states carry out transition, in transition, quantum destructive interference can occur for two transition probability amplitudes, cause altogether The absorption of the detection light detected at vibration frequency reduces, or even disappears.At this point, detection light can be propagated by medium, as Electromagnetically induced Transparency Phenomenon.

However, the EIT phenomenon of atomic system is limited by stable laser and low-temperature working condition, lead to chip level EIT phenomenon be difficult to realize.Currently, the class EIT phenomenon found in classical system receives very big concern, such as coupled resonance Device and plasmon structures etc..The class EIT resonance due to caused by Fano Linear is destructive is interfered, and cancellation between realization quantum is not needed Interfere applied experiment condition, provides a kind of implementation for the practical application of EIT phenomenon, be based especially on Meta Materials Plasma class EIT phenomenon causes concern, new device can be developed using this phenomenon, such as slower rays device and highly sensitive sensing Device etc..Compared to EIT phenomenon traditional between atom, the class EIT phenomenon in Meta Materials can be realized by different mechanism, and be made It is more easier to regulate and control, such as: optical dipole sub-antenna, closure ring resonator and split-ring resonator.Since EIT phenomenon has Slow light effect can realize slower rays device by the slow light effect of class EIT phenomenon in Meta Materials, to enhance the reality of EIT phenomenon Border application.However, when metamaterial structure unit geometric parameter once it is determined that, performance will be not available for tune and change, Strongly limit its application range.Therefore, tunable EIT Meta Materials research has attracted more and more concerns, probes into efficiently Convenient and fast tuning manner becomes focus of attention, it is made to have broader answer with fields such as nonlinear opticses in sensing, absorption Use prospect.

Currently, a variety of tunable EIT Meta Materials have been found and report, people's extensive concern and interest are caused.For example, 2011, Jingbo Wu and Biaobing Jin of Nanjing University et al. proposed that the plane of two based superconductors is tunable too Hertz EIT Meta Materials；2016, Quan Xu of University Of Tianjin et al. designed a kind of Terahertz EIT based on tunable semiconductor Meta Materials；2016, the Prakash Pitchappa of National University of Singapore propose it is a kind of based on MEMS tuning electromagnetism lure Lead transparent metamaterial；2017, it is super that Hang Su of Harbin Institute of Technology et al. proposes a kind of EIT based on liquid crystal tunable Surface switches.However, temperature range required for being tuned due to superconductor is lower, tunable semiconductor needs additional stable pumping Light, the complex process of MEMS technology, reliability is low, and liquid crystal material tuning is inflexible, it is difficult to obtain complete polarized light；In addition, Current tunable EIT Meta Materials are mostly single working bands.These defects bring very big difficulty to the practical application of EIT Meta Materials Degree, limits its application range.

Summary of the invention

It, can the invention aims to solve existing tunable Terahertz EIT Meta Materials slower rays device list working band Tuning range is narrow, structure and preparation process are complicated, external equipment is cumbersome, have a single function, reliability is low, active needed for energisation mode The optional narrow range of material and the small problem of linear properties, and a kind of graphene-gold of biobelt flexible choice regulation is provided Belong to slot Meta Materials Terahertz slower rays device.

A kind of graphene-metallic channel Meta Materials Terahertz slower rays device of biobelt flexible choice regulation, including terahertz Hereby slower rays device function structure, silicon dioxide insulating layer, silicon substrate and gate electrode structure；The Terahertz slower rays device function Structure is made of the metamaterial structure unit of periodic arrangement, and the metamaterial structure unit is by patterned metal slot structure and figure Patterned metal slot structure is arranged in graphical two graphene ribbons structure for two graphene ribbon structure composition of shapeization；The gate electrode Structure is made of the first metal electrode Pad1 and the second metal electrode Pad2, is provided with silicon dioxide insulator on the silicon substrate Layer, it is provided with graphical two graphene ribbons structure on silicon dioxide insulating layer, the graphical two graphene ribbons structure is the period Property arrangement；First metal electrode Pad1 and the second metal electrode Pad2 is separately positioned on the Terahertz slower rays device upper surface Two sides, the graphical two graphene ribbons structure of periodic arrangement respectively with the first metal electrode Pad1 and the second metal electrode Pad2 Connection；

Left side graphene in the first metal electrode Pad1 to the second direction metal electrode Pad2, Terahertz slower rays device Strip is to be interconnected by the first graphene ribbon structure, and connect to form first electrode with the first metal electrode Pad1；Along second Metal electrode Pad2 is to the first direction metal electrode Pad1, and corresponding right side graphene strip is by Terahertz slower rays device Two graphene ribbon structures interconnect, and connect to form second electrode with the second metal electrode Pad2；Wherein connection left side graphite The metal wire of alkene strip and the metal wire of connection right side graphene strip are not attached to, first electrode and second electrode difference；

The patterned metal slot structure is made of two pairs of horizontally disposed metallic channels and a metallic channel being vertically arranged, The two sides for the metallic channel being vertically arranged are arranged in two pairs of horizontally disposed metallic channels, along the metamaterial structural unit central Line, two pairs of horizontally disposed metallic channel horizontal directions are symmetrical, and vertical direction is asymmetric；The metallic channel being vertically arranged has one Run through the vertical gap of metamaterial structure unit along groove center line；The first graphene ribbon structure and the second graphene ribbon structure Size be length it is identical and of different size, be vertically disposed on two pairs of horizontally disposed metallic channels in the following, along the super material Expect the center line of structural unit, vertically disposed graphical two graphene ribbons structure level direction is symmetrical, and vertical direction is asymmetric； There is a vertical gap between the metal metamaterial structure adjacent cells.

A kind of graphene-metallic channel Meta Materials Terahertz slower rays device preparation side of biobelt flexible choice regulation Method is completed according to the following steps:

One, liner oxidation: silicon dioxide insulating layer is grown on low-doped HR-Si substrate using oxidation technology, is obtained Growth has the silicon substrate of silicon dioxide insulating layer；

Two, CVD method prepares graphene: first copper foil substrate is pre-processed with ferric nitrate, then using methane as carbon source, and argon Respectively as protection and reducing gas, copper foil substrate after the pre-treatment carries out heat treatment growth graphene for gas and hydrogen, obtains Stand-by graphene；

Three, graphene substrate shifts: then spin coating polymethyl methacrylate (PMMA) on the surface of graphene has spin coating The graphene of PMMA is placed in corrosion copper foil substrate in ferric chloride solution, the graphene after obtaining corrosion copper foil, then will corrode copper foil Graphene afterwards is cleaned multiple times in deionized water, the graphene after being cleaned, and finally has silica exhausted with growth The silicon substrate of edge layer fishes for graphene from deionized water, and removes the PMMA on graphene and secondary cleaning processing, completes Graphene in copper substrate, which is transferred to growth, to be had on the silicon substrate of silicon dioxide insulating layer；

Four, graphene is graphical: using mechanical spin-coating method on being transferred to the silicon substrate that growth has silicon dioxide insulating layer Graphene surface spin coating photoresist, then there is the graphene of photoresist to dry spin coating, be successively exposed, develop and Fixing obtains the graphical photoresist exposure mask of preparation graphene ribbon structure, then using oxygen plasma to the graphite of photoresist exposure mask Alkene performs etching, and finally removes photoresist using acetone soak and cleans, obtains patterned graphene band structure；

Five, metal patternization: mechanical spin-coating method spin coating is first used in the patterned graphene body structure surface that step 4 obtains Photoresist is successively exposed, develops and is fixed, and obtains the graphical photoresist exposure mask for preparing patterned metal slot structure, so Metal is deposited on the graphical photoresist exposure mask for preparing patterned metal slot structure using magnetron sputtering method afterwards, is finally placed in again 24 hours stripping metals and removal photoresist are impregnated in acetone soln, obtain patterned metal slot structure and gate electrode structure, it is complete Graphene-metallic channel Meta Materials Terahertz slower rays device the preparation regulated and controled at a kind of biobelt flexible choice.

Beneficial effects of the present invention:

One, traditional Terahertz Meta Materials are based on patterned metal periodic arrangement, since conductivity metal is fixed Constant, once fixed, corresponding resonance point is also fixed the structural parameters of metal structure unit with resonance manner, leads to its work Working frequency is fixed with electromagnetic property, is unable to flexible modulation electromagnetic property；A kind of biobelt flexible choice regulation of the present invention Graphene-metallic channel Meta Materials Terahertz slower rays device, by integrating graphene-structured in the structural unit of EIT Meta Materials, It is realized saturating to Meta Materials electromagnetically induced using the electrostatically-doped Fermi's energy for adjusting graphene to tune the conductivity of graphene The flexible control of bright window；

Two, it since current most of EIT Meta Materials work in one-segment, and cannot tune, significantly limit EIT The application range of Meta Materials；A kind of graphene-metallic channel Meta Materials Terahertz of biobelt flexible choice regulation of the present invention is slow Optical device, metal metamaterial structure unit are made of two pairs of horizontally disposed metallic channels and a metallic channel being vertically arranged, Two transparent windows are realized using dark-bright-dark electromagnetic field couples mode；And on this basis, by horizontally disposed at two pairs Dark modal metallic slot structure below integrate graphene ribbon structure, it is electrostatically-doped adjust graphene Fermi can, can flexible modulation The amplitude and working frequency of two transparent windows increase the function and application range of EIT Meta Materials.

Three, since traditional optical pumping excitation and thermal excitation mode can only carry out global regulation to overall structure, and cannot be real Current situation portion selective regulation；A kind of graphene-metallic channel Meta Materials Terahertz of biobelt flexible choice regulation of the present invention is slow Optical device uses two gate electrode structures, and in the edge setting gap of metamaterial structure unit and center upright hollow out strip Centre setting gap, it is therefore an objective to realize in structural unit and be electrically isolated between two pairs of horizontally disposed metal slot structures；Passability selection Property between gate electrode and substrate on-load voltage, can to two graphene strips carry out selectivity it is electrically doped, adjust graphene Fermi's energy carries out selective flexible modulation to two electromagnetically induced transparent window amplitudes of Meta Materials to realize, forms difference Reconstituted state, can flexible modulation electromagnetically induced reflection windows amplitude and group delay, form a variety of working conditions, can both carry out Single tape regulation, and can realize biobelt while regulate and control, it can also realize the asynchronous regulation of biobelt, expand working range, improve reality The property used；

Four, a kind of graphene-metallic channel Meta Materials Terahertz slower rays device of biobelt flexible choice regulation of the present invention, It is made of complementary type Meta Materials, by integrating graphene-structured in the structural unit of Meta Materials, electrically doped change graphene Fermi's energy has the characteristics that low in cost, simple process, tuning are easy.The present invention is integrated in metal structure using graphene Terahertz Meta Materials slower rays device is constructed, by Fermi's energy of electrostatically-doped tuning graphene strip, thus selectivity control stone Near-field coupling characteristic in the conductivity and metamaterial structure unit of black alkene strip between each element, is selectively realized to slow The amplitude at the transparent peak of the electromagnetically induced of optical device and group delay flexibly control.

The present invention can get a kind of graphene-metallic channel Meta Materials Terahertz slower rays device of biobelt flexible choice regulation Part.

Detailed description of the invention

Fig. 1 is a kind of graphene-metallic channel Meta Materials Terahertz slower rays of the biobelt flexible choice of embodiment one regulation The structural schematic diagram of device；

Fig. 2 is the top view of metamaterial structure unit；

Fig. 3 is the sectional view along two dotted line of figure；

Fig. 4 is that left side graphene strip Fermi can E_f1Become 0.7eV from 0.1eV, right side graphene strip Fermi can E_f2For When 0.1eV, in the variation of the reflectivity curve of 0.7THz to 1.1THz frequency range.

Fig. 5 is that left side graphene strip Fermi can E_f1When for 0.1eV, the Fermi of right side graphene strip can E_f2From 0.1eV When becoming 0.6eV, change in the reflectivity curve of 0.7THz to 1.1THz frequency range.

When Fig. 6 is that the Fermi of two sides graphene strip can become (0.6eV and 1eV) from (0.1eV and 0.08eV), The variation of reflectivity curve；

When Fig. 7 is that the Fermi of two sides graphene strip can become (0.6eV and 1eV) from (0.1eV and 0.08eV) Phase change；

When Fig. 8 is that the Fermi of two sides graphene strip can become (0.6eV and 1eV) from (0.1eV and 0.08eV) Group delay variations.

Wherein, 1 is silicon substrate, and 2 be silicon dioxide insulating layer, and 3 be graphical two graphene ribbons structure, and 3-1 is the first stone Black alkene band structure, 3-2 are the second graphene ribbon structure, and 4 be patterned metal slot structure, and 5 be the first metal electrode Pad1, and 6 are Second metal electrode Pad2.

Specific embodiment