Broadband Transmission Detection Device Based on Double-Layer Terahertz Metamaterial and Its Usage Method

Abstract

The present invention relates to a broadband transmission detection device based on a double-layer terahertz metamaterial and a method for using the same, which includes a first moving fixture and a second moving fixture oppositely arranged along the X-axis direction. The first moving fixture is installed on a one-dimensional moving platform that moves along the X-axis direction, and the one-dimensional moving platform is installed on an optical platform. A sample holder is provided on the first moving fixture, and a first central hollow is provided in the middle of the sample holder to facilitate the passage of terahertz waves. The second moving fixture is arranged on the vertical fixed seat of the terahertz spectroscopy system and moves along the Y-axis and Z-axis directions. A second central hollow is provided on the second moving fixture to facilitate the passage of terahertz waves. The double-layer terahertz metamaterials are respectively arranged on the sample holder and the second moving fixture. The present invention has a reasonable design, and during the experiment, the relative position between the metamaterials can be conveniently and quickly adjusted to better align the unit holes between the layers, reducing experimental errors, so as to achieve a better broadband filtering effect.

Description

Technical Field:

[0001] The present invention relates to a broadband transmission detection device based on a double-layer terahertz metamaterial and a method for using the same. Background Art:

[0002] Metamaterials have a unique ability to control electromagnetic waves, and can induce surface plasmon resonance in terahertz waves with a structural size in the micro-nano scale. They have become the core components of various terahertz functional devices. Terahertz devices based on metamaterials are widely used in fields such as antenna radars, waveguide transmissions, high-resolution imaging, high-power terahertz sources, and high-sensitivity sensing, and some breakthrough research results have been achieved. However, how to efficiently fabricate terahertz instruments with high precision, high integration, and practicality has become the key to the further development and application of terahertz technology.

[0003] Currently, due to the size of terahertz metamaterials being in the micron scale, their samples often need to be fabricated on a substrate with a thickness of hundreds of microns, which will cause losses during the detection process and show a peak blue shift in the spectrum. To address this defect, femtosecond laser ablation of metal films is used to fabricate substrate-free terahertz flexible metamaterials, which can avoid the peak blue shift caused by losses. At the same time, such substrate-free flexible metamaterials can be stacked to form multi-layer metamaterials, thereby making terahertz devices with high-performance such as high-sensitivity sensing and broadband filtering. However, due to the problem that the apertures of the interlayer units of the previous multi-layer terahertz metamaterials cannot be completely aligned, the ideal effect has not been achieved in experiments. Summary of the Invention:

[0004] The present invention makes improvements to the above-mentioned existing technical problems, that is, the technical problem to be solved by the present invention is to provide a broadband transmission detection device based on a double-layer terahertz metamaterial and a method for using the same, which is simple and reasonable in design and convenient for detecting the transmission module of the double-layer terahertz metamaterial.

[0005] To achieve the above object, the technical solution adopted by the present invention is: a broadband transmission detection device based on a double-layer terahertz metamaterial, including a first moving fixture and a second moving fixture arranged oppositely along the X-axis direction. The first moving fixture is installed on a one-dimensional moving platform that moves along the X-axis direction, and the one-dimensional moving platform is installed on an optical platform. A sample holder is vertically provided on the first moving fixture, and a first central hollow that penetrates along the X-axis direction and is conducive to the passage of terahertz waves is provided in the middle of the sample holder. The second moving fixture is arranged on a vertical fixing seat of the terahertz spectroscopy system and moves along the Y-axis and Z-axis directions. A second central hollow that penetrates along the X-axis direction and is conducive to the passage of terahertz waves is provided on the second moving fixture. The double-layer terahertz metamaterials are respectively arranged on the surfaces of the sample holder and the second moving fixture having the second central hollow.

[0006] Further, the first moving fixture includes a fixture base disposed on the moving part of the one-dimensional moving platform, and a locking assembly for locking the sample holder is provided on the top of the fixture base.

[0007] Further, the locking assembly includes an abutting part and a locking part respectively disposed on both sides of the sample holder. One side of the abutting part facing the locking part is in contact with the lower end of the sample holder. A first locking bolt is screwed in the middle of the locking part, and the first locking bolt abuts against the lower end of the sample holder to lock the sample holder on the abutting part.

[0008] Further, a relief opening for accommodating the second moving fixture is provided in the middle of the abutting part; the second moving fixture includes an L-shaped connecting seat and a T-shaped connecting seat. The vertical side of the L-shaped connecting seat is located in the relief opening, and a second central hollow is provided in the vertical side of the L-shaped connecting seat; the T-shaped connecting seat is horizontally arranged, and the horizontal side of the T-shaped connecting seat is connected to the horizontal side of the L-shaped connecting seat.

[0009] Further, an adjustment long slot extending in the X-axis direction is provided on the horizontal side of the L-shaped connecting seat, and a second locking bolt is inserted into the adjustment long slot. The second locking bolt passes through the horizontal side of the T-shaped connecting seat and is screwed with a locking nut.

[0010] Further, the stroke of the one-dimensional moving platform is 25 mm, and the step pitch is 10 μm.

[0011] Another technical solution adopted by the present invention is: a usage method of a broadband transmission detection device based on a double-layer terahertz metamaterial. The usage method is carried out according to the following steps:

[0012] (1) Fix the one-dimensional moving platform on the optical platform, and vertically install the sample holder with a layer of terahertz metamaterial attached thereto on the first moving fixture;

[0013] (2) Place the second moving fixture on the vertical fixing seat of the terahertz spectroscopy system, and attach another layer of terahertz metamaterial to the surface of the second moving fixture with a second central hollow;

[0014] (3) Use the one-dimensional displacement platform to control the movement of the first layer of terahertz metamaterial in the X-axis direction, and at the same time use the terahertz spectroscopy detection system to control the movement of the second layer of terahertz metamaterial in the Y-axis and Z-axis directions to align the periodic units between the two layers of terahertz metamaterials and reduce experimental errors;

[0015] (4) The terahertz emitter and terahertz detector of the terahertz optical system are respectively arranged on both sides of the broadband transmission detection device. The terahertz wave emitted by the terahertz emitter vertically enters from one side of the sample holder, passes through two layers of terahertz metamaterials and generates a reaction, then vertically exits from the side of the second moving clamp facing away from the sample holder, and the signal is received by the terahertz detector and then transmitted to the signal processing system to form the terahertz detection spectrum of the sample.

[0016] Compared with the prior art, the present invention has the following effects: The structure of the present invention is simple and reasonable. It can fix two layers of terahertz metamaterials, use a one-dimensional displacement platform to control the first layer of terahertz metamaterial to move in the X-axis direction, and at the same time use the terahertz spectrum detection system to control the second layer of terahertz metamaterial to move in the Y-axis and Z-axis directions. During the experiment, the relative position between the metamaterials can be conveniently and quickly adjusted to make the unit holes between the layers better aligned, reducing the experimental error, so as to achieve a better broadband filtering effect. Brief Description of the Drawings:

[0017] Figure 1 is a three-dimensional structural schematic diagram of an embodiment of the present invention;

[0018] Figure 2 is a front view structural schematic diagram of an embodiment of the present invention;

[0019] Figure 3 is a left view structural schematic diagram of an embodiment of the present invention;

[0020] Figure 4 is a top view structural schematic diagram of an embodiment of the present invention;

[0021] Figure 5 is a schematic diagram of the test principle of the terahertz spectrum system in an embodiment of the present invention.

[0022] In the figure:

[0023] 1 - T-shaped connecting seat; 2 - second locking bolt; 3 - L-shaped connecting seat; 4 - fixture base; 5 - sample holder; 6 - first locking bolt; 7 - one-dimensional displacement platform; 8 - connecting base; 9 - locking nut; 10 - first central hollow; 11 - second central hollow; 12 - abutting portion; 13 - locking portion; 14 - relief opening; 15 - adjusting long slot; 16 - first moving clamp; 17 - second moving clamp. Specific Embodiments:

[0024] The present invention will be further described in detail below with reference to the drawings and specific embodiments.

[0025] In the description of the present invention, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0026] like Figures 1 to 5 As shown, the present invention is a broadband transmission detection device based on a double-layer terahertz metamaterial, the broadband transmission detection device is arranged between a terahertz emitter and a terahertz detector of a terahertz optical system (not shown in the figure), and specifically includes a first movable fixture 16 and a second movable fixture 17 which are arranged relatively along the X-axis direction, the first movable fixture 16 is installed on a one-dimensional movable platform 7, the one-dimensional movable platform 7 drives the first movable fixture 16 to move along the X-axis direction, the one-dimensional movable platform 7 is installed on an optical platform (not shown in the figure), a sample holder 5 is vertically arranged on the first movable fixture 16, and a through hole is provided in the middle of the sample holder 5 which is through along the X-axis direction and is conducive to the passage of terahertz waves The first central hollow 10 of the terahertz spectroscopy system is provided; the second mobile fixture 17 is provided on the vertical fixed seat provided by the terahertz spectroscopy system, and the second mobile fixture 17 moves along the Y-axis and Z-axis directions with the vertical fixed seat provided by the terahertz spectroscopy system. The second mobile fixture 17 is provided with a second central hollow 11 which is through along the X-axis direction and is convenient for the terahertz wave to pass through. The double-layer terahertz metamaterial is respectively provided on the surface of the sample holder 5 and the second mobile fixture 17 with the second central hollow 11, specifically: the first layer of terahertz metamaterial is attached to the side surface of the sample holder facing the second mobile fixture, and the second layer of terahertz metamaterial is attached to the side surface of the second mobile fixture facing the sample holder. When working, the terahertz wave emitted by the Hertz emitter is vertically incident from one side of the sample holder, passes through the two layers of terahertz metamaterials and reacts, and then vertically emitted from the side of the second mobile fixture facing away from the sample holder, and the signal is received by the terahertz detector, and then transmitted to the signal processing system to form the terahertz detection spectrum of the sample. The detection device can generate surface plasma resonance in the double-layer metamaterial sample by terahertz waves, thus realizing broadband filtering. It has a simple structure and is easy to debug. At the same time, it can realize flexible control of multi-layer micro-nano electromagnetic materials in transmission detection, and has potential engineering application value in analyzing the physical and chemical properties of materials.

[0027] It should be noted that the terahertz emitter, terahertz detector and sample are kept in a straight line to ensure that the terahertz wave can smoothly pass through the two layers of material and produce a reaction. The simple unit structure can induce the terahertz incident wave to generate localized surface plasmons in the metal through-hole, which is characterized by a high transmittance resonance peak in the spectrum.

[0028] In this embodiment, the first movable fixture 16 includes a fixture base 4 arranged on the movable part of the one-dimensional movable platform 7, and a locking assembly for locking the sample holder 5 is provided on the top of the fixture base 4, and the locking assembly includes an abutment portion 12 and a locking portion 13 respectively arranged on both sides of the sample holder 5, and a side of the abutment portion 12 facing the locking portion 13 is in contact with the lower end of the sample holder 5, and a first locking bolt 6 is screwed on the middle part of the locking portion 13, and the first locking bolt 6 is in contact with the lower end of the sample holder 5 to lock the sample holder in the abutment portion, and the sample holder is fixed by the cooperation of the first locking bolt and the abutment portion.

[0029] In this embodiment, the middle of the abutting portion 12 is provided with a clearance opening 14 for accommodating the second movable fixture; the second movable fixture 17 includes an L-shaped connection seat 3 and a T-shaped connection seat 1, the vertical side of the L-shaped connection seat 3 is located in the clearance opening 14, and the vertical side of the L-shaped connection seat 3 is provided with a second central hollow 11; the T-shaped connection seat 1 is arranged horizontally, and the horizontal side of the T-shaped connection seat 1 is connected to the horizontal side of the L-shaped connection seat 3. The L-shaped connection seat and the T-shaped connection seat are combined and placed on the vertical fixing seat of the terahertz spectroscopy system, and the movement in two directions (Z axis and Y axis) is realized by the control software of the terahertz spectroscopy system.

[0030] In this embodiment, the horizontal edge of the L-shaped connecting seat 3 is provided with an adjustment slot 15 extending along the X-axis direction, and a second locking bolt 2 is passed through the adjustment slot 15. The second locking bolt 2 passes through the horizontal edge of the T-shaped connecting seat 1 and is threadedly connected to the locking nut 9.

[0031] In this embodiment, the one-dimensional moving platform 7 has a stroke of 25 mm and a step distance of 10 μm, which can realize the movement of the sample in the X-axis direction.

[0032] In this embodiment, the first locking bolt 6 is M6, and its thread pitch is 30 mm.

[0033] In this embodiment, the second locking bolt 2 is M6, and its thread pitch is 25 mm.

[0034] In this embodiment, the one-dimensional displacement platform 7 and the optical platform are connected via a connecting base 8 .

[0035] In this embodiment, the size of the first central hollow is 15×15 mm.2 .

[0036] In this embodiment, the double-layer terahertz metamaterial is fabricated by femtosecond laser direct writing technology, and the processing area is about 10×10 mm 2 .

[0037] In this embodiment, the first moving fixture, the second moving fixture, the sample holder, and the connection base are all manufactured using PLA three-dimensional printing material.

[0038] In this embodiment, the usage method of the broadband transmission detection device based on the double-layer terahertz metamaterial is carried out according to the following steps:

[0039] (1) Fix the one-dimensional moving platform 7 on the optical platform through the connection base 8, and vertically install the sample holder with a layer of terahertz metamaterial attached thereon on the first moving fixture 16;

[0040] (2) Place the second moving fixture 17 on the vertical fixing seat of the terahertz spectroscopy system, and attach another layer of terahertz metamaterial on the surface of the second moving fixture 17 with the second central hollow 11;

[0041] (3) Use the one-dimensional displacement platform 7 to control the movement of the first layer of terahertz metamaterial in the X-axis direction, and at the same time use the terahertz spectroscopy detection system to control the movement of the second layer of terahertz metamaterial in the Y-axis and Z-axis directions, so that the periodic units between the two layers of terahertz metamaterials are aligned to reduce experimental errors;

[0042] (4) Place the terahertz emitter and the terahertz detector of the terahertz optical system on both sides of the broadband transmission detection device respectively, ensure that the terahertz emitter, the terahertz detector and the sample are kept on the same straight line, and ensure that the terahertz wave can smoothly pass through the two layers of materials and generate a reaction; the terahertz wave emitted by the terahertz emitter is perpendicularly incident from one side of the sample holder, passes through the two layers of terahertz metamaterials respectively and generates a reaction, then perpendicularly exits from the side of the second moving fixture facing away from the sample holder, and the signal is received by the terahertz detector and then transmitted to the signal processing system to form the terahertz detection spectrum of the sample.

[0043] The advantages of the present invention are as follows:

[0044] (1) Utilize the terahertz wave passing through the two layers of metamaterials to generate surface plasmon polaritons and Fabry-Perot resonance phenomena, thereby achieving the effect of broadband filtering;

[0045] (2) It is applicable to the measurement of multi-layer metamaterial structures and has potential engineering application value in analyzing its filtering and sensing performance;

[0046] (3) By taking advantage of the high-precision positioning feature of the one-dimensional moving platform and the terahertz spectroscopy detection system, during the sample detection process, the unit holes between the two layers of metamaterials can be conveniently and quickly aligned to the optimal position, maximizing the intensity of the terahertz signal detected by the terahertz detector.

[0047] (4) Adopt a method that can utilize rapid prototyping by three-dimensional printing. Use PLA three-dimensional printing material to process components such as fixtures, sample holders, and bases, significantly reducing the processing cycle, cost, and the overall weight of the detection device.

[0048] If the present invention discloses or involves components or structural parts that are fixedly connected to each other, then, unless otherwise stated, the fixed connection can be understood as: a detachable fixed connection (such as using bolts or screws), or it can also be understood as: a non-detachable fixed connection (such as riveting or welding). Of course, the mutually fixed connection can also be replaced by an integral structure (such as manufactured by integral casting process) (except when it is clearly impossible to use the integral forming process).

[0049] Additionally, in any of the technical solutions disclosed in the present invention above, the terms used to represent positional relationships or shapes, unless otherwise stated, include states or shapes that are approximate, similar, or close to them.

[0050] Any component provided by the present invention can either be assembled from multiple separate components or be a single component manufactured by an integral forming process.

[0051] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them; although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that: it is still possible to modify the specific implementation manners of the present invention or make equivalent replacements for some technical features; without departing from the spirit of the technical solutions of the present invention, they should all be covered within the scope of the technical solutions claimed by the present invention.

Claims

1. A broadband transmission detection device based on a double-layer terahertz metamaterial, characterized in that: It includes a first moving clamp and a second moving clamp arranged oppositely along the X-axis direction. The first moving clamp is installed on a one-dimensional moving platform that moves along the X-axis direction. The one-dimensional moving platform is installed on an optical platform. A sample holder is vertically provided on the first moving clamp. A first central hollow that penetrates along the X-axis direction and is conducive to the penetration of terahertz waves is provided in the middle of the sample holder; the second moving clamp is arranged on the vertical fixed seat of the terahertz spectroscopy system and moves along the Y-axis and Z-axis directions. A second central hollow that penetrates along the X-axis direction and is conducive to the penetration of terahertz waves is provided on the second moving clamp. The double-layer terahertz metamaterial is respectively arranged on the surfaces of the sample holder and the second moving clamp that have the second central hollow; The first moving clamp includes a clamp base arranged on the moving part of the one-dimensional moving platform. A locking component for locking the sample holder is provided on the top of the clamp base; The locking component includes an abutting part and a locking part respectively arranged on both sides of the sample holder. The side surface of the abutting part facing the locking part is in contact with the lower end of the sample holder. A first locking bolt is screwed in the middle of the locking part. The first locking bolt abuts against the lower end of the sample holder to lock the sample holder on the abutting part.

2. A broadband transmission detection device based on a double-layer terahertz metamaterial according to claim 1, characterized in that: A relief opening for accommodating the second moving clamp is provided in the middle of the abutting part; the second moving clamp includes an L-shaped connecting seat and a T-shaped connecting seat. The vertical side of the L-shaped connecting seat is located in the relief opening, and a second central hollow is provided in the vertical side of the L-shaped connecting seat; the T-shaped connecting seat is arranged horizontally, and the horizontal side of the T-shaped connecting seat is connected to the horizontal side of the L-shaped connecting seat.

3. A broadband transmission detection device based on a double-layer terahertz metamaterial according to claim 2, characterized in that: An adjusting long groove extending along the X-axis direction is provided on the horizontal side of the L-shaped connecting seat. A second locking bolt is inserted into the adjusting long groove. The second locking bolt passes through the horizontal side of the T-shaped connecting seat and is screwed with a locking nut.

4. A broadband transmission detection device based on a double-layer terahertz metamaterial according to claim 1, characterized in that: The stroke of the one-dimensional moving platform is 25 mm, and the step distance is 10 μm.

5. A method for using a broadband transmission detection device based on a double-layer terahertz metamaterial, characterized in that: It includes using the broadband transmission detection device based on a double-layer terahertz metamaterial described in any one of claims 1-2. The using method is carried out according to the following steps: (1) Fix the one-dimensional moving platform on the optical platform, and vertically install the sample holder with a layer of terahertz metamaterial attached on the first moving clamp; (2) Place the second moving clamp on the vertical fixed seat of the terahertz spectroscopy system, and attach another layer of terahertz metamaterial on the surface of the second moving clamp that has the second central hollow; (3) Use a one-dimensional displacement platform to control the movement of the first layer of terahertz metamaterial in the X-axis direction, and at the same time use a terahertz spectroscopy detection system to control the movement of the second layer of terahertz metamaterial in the Y-axis and Z-axis directions to align the periodic units between the two layers of terahertz metamaterials and reduce experimental errors; (4) Place the terahertz emitter and terahertz detector of the terahertz optical system on both sides of the broadband transmission detection device respectively. The terahertz wave emitted by the terahertz emitter is perpendicularly incident from one side of the sample holder, passes through the two layers of terahertz metamaterials respectively and generates reactions, then perpendicularly exits from the side of the second moving fixture facing away from the sample holder, and the signal is received by the terahertz detector and then transmitted to the signal processing system to form the terahertz detection spectrum of the sample.

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