CN102902126A - Light-operated Terahertz wave speed-sensitive switch device and method thereof - Google Patents

Abstract

The invention discloses a light-controlled terahertz wave high-speed switch device and a method thereof. It includes a terahertz wave input terminal, a laser input terminal, and N×N structural units, where N is a natural number; N×N structural units are periodically arranged on a plane perpendicular to the input direction of the terahertz wave. The structural units include metal structural layers, The substrate and the metal film layer, the metal structure layer is connected to the substrate, the metal structure layer is composed of an X-shaped metal piece and four T-shaped metal pieces, the X-shaped metal piece vertically intersects at the center of the metal structure layer, and the four T-shaped metal pieces The ends of the piece are respectively connected with the four ends of the X-shaped metal piece, and the other side of the substrate is connected with the metal film layer. The light-controlled terahertz wave high-speed switch device of the present invention has a simple and compact structure, is convenient to manufacture, has a fast response speed, and is convenient to adjust, and meets application requirements in fields such as terahertz wave imaging, medical diagnosis, environmental monitoring, and broadband mobile communication.

Description

Optically controlled terahertz wave high-speed switching device and method thereof

technical field

The invention relates to the technical field of terahertz wave applications, in particular to an optically controlled terahertz wave high-speed switch device and a method thereof.

Background technique

Terahertz waves refer to electromagnetic waves with a frequency of 0.1-10 THz and a wavelength of 3000-30 μm. It coincides with millimeter waves at long wavelengths and with infrared at short wavelengths. Terahertz waves occupy a very special position in the electromagnetic spectrum. Since the problem of terahertz wave source has not been well solved for a long time, people have very limited understanding of the nature of electromagnetic radiation in this band, and the development of terahertz wave science and technology has been greatly restricted, so that this wave band is called electromagnetic wave. The "terahertz gap" (Terahertz Gap) in the spectrum, so that its application potential has not been realized. At present, the terahertz wave source and detection device have been successfully developed in the world. Studies have found that terahertz waves, as a high-frequency electromagnetic wave, are safer than X-rays and are used in many fields such as medical diagnosis, security inspection, biomedicine, agriculture, space astronomy, non-destructive testing, and terahertz communication. Due to the wide application prospects of terahertz waves, countries all over the world attach great importance to the research of terahertz wave science and technology.

The development of terahertz wave generation and detection technology has greatly promoted the development of terahertz technology and its applications. Terahertz technology has broad application prospects in medical diagnosis, environmental monitoring, broadband mobile communication, astronomy and other fields. When applying terahertz technology to solve practical problems, functional devices such as terahertz waveguides and switches are essential devices to realize the functions of the entire system. However, the functional devices of terahertz waves are the focus and difficulty in the application of terahertz wave science and technology, and the research on functional devices of terahertz waves has been gradually carried out at home and abroad. Existing terahertz wave functional devices are still very few, and they are usually complex in structure, large in size and expensive, so miniaturized and compact terahertz wave devices are the key to the application of terahertz wave technology.

Terahertz wave switch is a very important terahertz wave functional device, which has a wide range of applications in terahertz wave applications such as terahertz wave imaging, terahertz wave medical diagnosis, terahertz wave communication, and terahertz wave space astronomy. Foreground, but the existing terahertz wave switch structure is complex, difficult to manufacture, expensive, large loss, slow response. Therefore, it is urgent to develop a terahertz wave switch with simple structure, convenient fabrication and fast response to meet the needs of practical terahertz applications.

Contents of the invention

The purpose of the present invention is to overcome the deficiencies of the prior art, and provide a light-controlled terahertz wave high-speed switch device and its method.

In order to achieve the above object, technical scheme of the present invention is as follows:

The light-controlled terahertz wave high-speed switch device includes a terahertz wave input terminal, a laser input terminal, and N×N structural units, where N is a natural number; N×N structural units are periodically arranged on a plane perpendicular to the input direction of the terahertz wave, The structural unit includes a metal structure layer, a substrate and a metal film layer. The metal structure layer is connected to the substrate. The metal structure layer is composed of an X-shaped metal piece and four T-shaped metal pieces. The X-shaped metal piece is vertically intersected at the center of the metal structure layer. position, the ends of the four T-shaped metal parts are respectively connected with the four ends of the X-shaped metal part, and the other side of the substrate is connected with the metal film layer.

The front view of the periodically arranged N×N structural units is a square, and the side length of the square is 170 μm to 180 μm. The material of the metal structure layer is gold with a thickness of 0.8 μm to 1.0 μm. The matrix is a polymer material with a thickness of 105 μm to 110 μm. The material of the metal thin film layer is gold with a thickness of 0.8 μm to 1.0 μm. The X-shaped metal piece has a length of 68 μm to 70 μm and a width of 12 μm to 13 μm; the T-shaped metal piece has a length of 68 μm to 70 μm, a width of 54 μm to 56 μm, and a metal line width of 8 μm to 9 μm.

The optically controlled terahertz wave high-speed switching method is: when the terahertz wave is input from the input end of the terahertz wave, the terahertz wave with a frequency of 1.349 THz is driven by N×N structures under the condition that no external laser is input from the laser input end. The unit absorbs, there is no reflection. When an external laser is input from the laser input end, due to the kerr effect of the polymer material matrix, the refractive index of the polymer material matrix will change rapidly, and the frequency value corresponding to the absorption peak of the device will change, and the previously absorbed frequency The 1.349THz terahertz wave is reflected back to the terahertz wave input end, from no external laser input to external laser input, so that the 1.349THz terahertz wave is reflected from no reflection to all reflection, realizing the high-speed optically controlled terahertz wave The disconnection of the switch.

The light-controlled terahertz wave high-speed switch device of the present invention has a simple and compact structure, is convenient to manufacture, has a fast response speed, and is convenient to adjust, and meets application requirements in fields such as terahertz wave imaging, medical diagnosis, environmental monitoring, and broadband mobile communication.

Description of drawings:

Figure 1 is a schematic diagram of the structural unit of an optically controlled terahertz wave high-speed switching device;

Figure 2 is a schematic diagram of the metal structure layer of the light-controlled terahertz wave high-speed switch device;

Fig. 3 is a front view of an optically controlled terahertz wave high-speed switching device;

Fig. 4 is a graph of absorption curves of an optically controlled terahertz wave high-speed switching device under different intensities of laser irradiation.

Detailed ways

As shown in Figures 1 to 3, the light-controlled terahertz wave high-speed switch device is characterized in that it includes a terahertz wave input terminal 1, a laser input terminal 2, and N×N structural units 3, where N is a natural number; N×N structures The unit 3 is periodically arranged on a plane perpendicular to the input direction of the terahertz wave. The structural unit 3 includes a metal structure layer 4, a substrate 5 and a metal film layer 6. The metal structure layer 4 is connected to the substrate 5. The metal structure layer 4 is composed of an X-shaped The metal piece 7 is composed of four T-shaped metal pieces 8, the X-shaped metal piece 7 is vertically intersected at the center of the metal structure layer 4, and the ends of the four T-shaped metal pieces 8 are respectively connected to the four ends of the X-shaped metal piece 7 , the other side of the substrate 5 is connected to the metal thin film layer 6 .

The front view of the periodically arranged N×N structural units 3 is a square, and the side length of the square is 170 μm to 180 μm. The material of the metal structure layer 4 is gold, with a thickness of 0.8 μm to 1.0 μm. The base 5 is a polymer material with a thickness of 105 μm to 110 μm. The material of the metal thin film layer 6 is gold, with a thickness of 0.8 μm to 1.0 μm. The X-shaped metal piece 7 has a length of 68 μm to 70 μm and a width of 12 μm to 13 μm; the T-shaped metal piece 8 has a length of 68 μm to 70 μm, a width of 54 μm to 56 μm, and a metal line width of 8 μm to 9 μm.

The optically controlled terahertz wave high-speed switching method is: when the terahertz wave is input from the terahertz wave input terminal 1, and the terahertz wave with a frequency of 1.349 THz is input by N×N A structural unit 3 absorbs and does not reflect. When an external laser is input from the laser input terminal 2, due to the kerr effect of the polymer material matrix 5, the refractive index of the polymer material matrix 5 will change rapidly, and the frequency value corresponding to the absorption peak of the device will change, which was previously The absorbed terahertz wave with a frequency of 1.349THz is reflected back to the terahertz wave input terminal 1, from no external laser input to external laser input, so that the terahertz wave with a frequency of 1.349THz changes from no reflection to full reflection, realizing light control On-off of high-speed switching of terahertz waves.

Example 1

Optically controlled terahertz wave high-speed switch:

Select the number of structural units N=50. The front view of periodically arranged N×N structural units is a square, and the side length of the square is 175 μm. The metal structure layer is made of gold with a thickness of 0.8 μm. The substrate is a polymer material with a thickness of 110 μm. The material of the metal thin film layer is gold, and the thickness is 1.0 μm. The X-shaped metal piece has a length of 70 μm and a width of 12 μm; the T-shaped metal piece has a length of 69.5 μm, a width of 55 μm, and a metal line width of 8 μm. Since there is a metal thin film layer behind the switching device, the terahertz wave cannot be transmitted out. When the terahertz wave is input from the terahertz wave input end, under the condition that no external laser is input from the laser input end, the terahertz wave of a certain frequency is absorbed without reflection. When an external laser is input from the laser input end, due to the kerr effect of the polymer material matrix, the refractive index of the polymer material matrix will change rapidly, and the frequency value corresponding to the absorption peak of the designed device will change. The absorbed terahertz wave of a specific frequency is reflected back to the input end of the terahertz wave. From no external laser input to external laser input, no reflection to full reflection of the specific frequency terahertz wave can be realized, and the optically controlled high-speed switch of the terahertz wave is realized. break function. When the laser is irradiated on the blank area of the metal structure layer, the refractive index of the polymer material changes rapidly under different intensity laser irradiation conditions, so the absorption peaks of different frequencies can be obtained quickly. It can be seen from Figure 4 that when there is no external laser input, that is, when the external laser input is 0, the refractive index of the polymer matrix is 1.59, and the absorption rate of terahertz wave with frequency f=1.349THz is 99.93%, and the reflection rate is 0.07%. . When there is an external laser input, that is, when the external laser input intensity is 18.75MW/cm ² , the refractive index of the polymer matrix is 1.62. At this time, the frequency corresponding to the maximum absorption peak is 1.324THz, and the corresponding absorption rate is 99.59%. At this time, the absorption rate of the terahertz wave with a specific frequency f=1.349THz is only 0.74%, because the terahertz wave cannot be transmitted, so the reflection rate is 99.26%, which realizes the terahertz wave of f=1.349THz Quick absorption or reflection. Due to the extremely fast response time of the polymer material, the absorption or reflection of terahertz waves of different frequencies can be quickly realized by changing the laser intensity, and the on-off function of the high-speed switch is realized.

Claims (7)

1. a light-operated THz wave high-speed switching arrangement is characterized in that comprising THz wave input end (1), laser input end (2), N * N structural unit (3), and N is natural number; N * N structural unit (3) periodic arrangement is on the plane vertical with the THz wave input direction, structural unit (3) comprises structured metal layer (4), matrix (5) and metal film layer (6), structured metal layer (4) links to each other with matrix (5), structured metal layer (4) is comprised of an X-type metalwork (7) and four T-shaped metalworks (8), X-type metalwork (7) is vertically intersected on the center of structured metal layer (4), four T-shaped metalworks (8) end links to each other with four end points of X-type metalwork (7) respectively, and the opposite side of matrix (5) links to each other with metal film layer (6).

2. a kind of light-operated THz wave high-speed switching arrangement as claimed in claim 1 is characterized in that the front elevation of N * N the structural unit (3) of described periodic arrangement is square, and the square length of side is 170 μ m ~ 180 μ m.

3. a kind of light-operated THz wave high-speed switching arrangement as claimed in claim 1 is characterized in that the material of described structured metal layer (4) is gold, and thickness is 0.8 μ m ~ 1.0 μ m.

4. a kind of light-operated THz wave high-speed switching arrangement as claimed in claim 1 is characterized in that described matrix (5) is polymeric material, and thickness is 105 μ m ~ 110 μ m.

5. a kind of light-operated THz wave high-speed switching arrangement as claimed in claim 1 is characterized in that the material of described metal film layer (6) is gold, and thickness is 0.8 μ m ~ 1.0 μ m.

6. a kind of light-operated THz wave high-speed switching arrangement as claimed in claim 1, the length that it is characterized in that described X-type metalwork (7) is 68 μ m ~ 70 μ m, wide is 12 μ m ~ 13 μ m; The length of T-shaped metalwork (8) is 68 μ m ~ 70 μ m, and wide is 54 μ m ~ 56 μ m, and the metal live width is 8 μ m ~ 9 μ m.

7. light-operated THz wave speed-sensitive switch method that use is installed as claimed in claim 1, it is characterized in that when THz wave is inputted from THz wave input end (1), do not adding laser under the condition of laser input end (2) input, frequency is that the THz wave of 1.349THz is absorbed by N * N structural unit (3), not reflection; When adding laser and input from laser input end (2), because the kerr effect of polymeric material matrix (5), the refractive index of polymeric material matrix (5) can change rapidly, the frequency values that the absorption peak of described device is corresponding changes, absorbed frequency is that the THz wave of 1.349THz is reflected back THz wave input end (1) before, by being input to and adding laser input without adding laser, make frequency be the THz wave of 1.349THz by no reflection events to all reflections, realized the open close of light-operated THz wave speed-sensitive switch.

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