2-bit graphene encoder with multilayer structure

Abstract

The invention discloses a 2-bit encoder with a multilayer structure, which relates to the technical field of encoder devices in the terahertz communication field, and is characterized in that a periodic array unit is formed by a graphene layer 1, a substrate layer 1, a graphene layer 2 and a substrate layer 2; the first graphene layer comprises four first graphene units, and the second graphene layer comprises four second graphene units; the graphene second unit comprises a graphene first elliptical unit and a graphene second elliptical unit. The method has the advantages of high coding speed, simplicity in operation, simplicity and convenience in preparation and the like, and has a good application prospect.

Description

Technical Field

[0001] The present invention relates to the field of terahertz frequency band communications, and in particular to a 2-bit graphene encoder with a multi-layer structure. Background Art

[0002] The terahertz frequency band is an electromagnetic wave with a frequency range of 0.1-10THz. In recent years, due to the improvement of terahertz sources and detection equipment, terahertz technology has developed rapidly. Compared with microwave communication, the terahertz frequency band has higher bandwidth and information capacity, so it can meet the communication needs of modern society.

[0003] The existing modulation methods in the terahertz frequency band are basically implemented on a single substrate. The drawing and manufacturing of complex patterns on a substrate poses a great challenge to the existing preparation process. At the same time, the difficulty of controlling different patterns on a substrate will also increase. The difficulty of manufacturing, the difficulty of control and the high price are the factors that limit the preparation of single-substrate metamaterials. In addition, there is also a method of modulation by controlling the light source to electrically illuminate the specific pattern of the metamaterial, but this method has very strict requirements on the optical path and higher requirements on the sensitivity of the detector, so this method is also greatly restricted.

[0004] With the development of modern society, the requirements for communication technology are gradually increasing, and an encoder with low requirements on the preparation process and simple encoding method is needed. Summary of the invention

[0005] In view of the above-mentioned shortcomings of the prior art, the purpose of the present invention is to provide a multi-layered 2-bit graphene encoder that can realize the function of 2-bit encoding in the terahertz frequency band and has the advantages of fast encoding speed, simple operation, and easy preparation.

[0006] To achieve the above-mentioned purpose and other related purposes, the present invention provides a 2-bit graphene encoder with a multi-layer structure, characterized in that the encoder is a square structural unit arranged periodically; in one unit structure, it includes: a graphene layer 1, a substrate layer 1, a graphene layer 2 and a substrate layer 2; the graphene layer 1 is arranged on the upper surface of the substrate layer 1, the substrate layer 1 is arranged on the upper surface of the graphene layer 2, and the graphene layer 2 is arranged on the upper surface of the substrate layer 2; the graphene layer 1 includes 4 first graphene units, and the graphene layer 2 includes 4 second graphene units; the 4 first graphene units are symmetrical about the center of the intersection of the diagonals of the device, and the 4 second graphene units are symmetrical about the center of the intersection of the diagonals of the device; the first graphene unit and the second graphene unit do not overlap in a vertical position, the second graphene unit includes a first graphene elliptical module and a second graphene elliptical module, and the second graphene elliptical module is formed by rotating the first graphene elliptical module by 90 degrees along the boundary point.

[0007] Optionally, the side length of the square structural unit is 8 to 15 microns; the materials of substrate layer 1 and substrate layer 2 are both silicon dioxide, with the same thickness of 0.2 to 10 microns; the thickness of graphene layer 1 and graphene layer 2 is the same and less than the thickness of substrate layer 1 and substrate layer 2.

[0008] Optionally, the first graphene unit is a rectangle with a length of 3 to 4 microns and a width of 0.8 to 1.2 microns, and the boundary between the first graphene unit and the substrate 1 layer does not overlap; the first graphene elliptical module is a quarter of an ellipse with a major axis of 3 to 4 microns and a minor axis of 0.3 to 0.9 microns.

[0009] Optionally, the 2-bit graphene encoder of the multi-layer structure can form two transmission troughs at frequency A and frequency B, and can achieve a 2-bit encoding function at the frequencies of the two transmission troughs.

[0010] As described above, the present invention is a 2-bit graphene encoder with a multi-layer structure, which has the following effects: the present invention is a coding device suitable for the terahertz frequency band communication field, can complete the 2-bit coding function, and has the characteristics of fast coding speed, simple operation, and easy preparation. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] In order to further illustrate the contents described in the present invention, the specific embodiments of the present invention are further described in detail below in conjunction with the accompanying drawings. It should be noted that these drawings are only typical examples and should not be regarded as limiting the scope of the present invention.

[0012] Figure 1 Schematic diagram of a unit structure of a multi-layer 2-bit graphene encoder in one embodiment of the present invention.

[0013] Figure 2 This is a terahertz transmission spectrum of a 2-bit graphene encoder with a multi-layer structure in one embodiment of the present invention. DETAILED DESCRIPTION

[0014] In order to make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the technical scheme in the embodiments of the present application will be described in detail and completely in combination with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. The components of the embodiments of the present application described and shown in the drawings here can be arranged and designed in various different configurations. It should be noted that the directional terms mentioned in the examples, such as "upper", "lower", "middle", "left", "right", "front", "back", etc., are only reference to the directions of the drawings. Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the application for which protection is claimed, but only represents the selected embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without making creative work belong to the scope of protection of the present application.

[0015] An implementation example of a multi-layer 2-bit graphene encoder Figure 1 As shown, the side length P of the square unit structure is 10 microns. The thickness h of the substrate 1 layer and the substrate 2 layer is 0.2 microns, and the thickness of the graphene 1 layer and the graphene 2 layer is 1 nanometer. The first graphene unit is a rectangle with a length L of 3.5 microns and a width d of 1 micron. The first graphene elliptical module is a quarter of an ellipse with a major axis R2 of 3.5 microns and a minor axis R1 of 0.5 microns. In this example, two transmission troughs are formed at 3.407THz and 5.308THz.

[0016] In this example, the Fermi levels of the graphene 1 layer and the graphene 2 layer are used as input ends, and the Fermi levels of the graphene 1 layer and the graphene 2 layer can be independently controlled. In this example, the graphene Fermi level is 0.8eV, which is a "0" logic state, and the graphene Fermi level is 1.1eV, which is a "1" logic state. The output end uses 2-bit binary 00, 01, 10 and 11 as the four digital states of the 2-bit graphene encoder of the multilayer structure, and the first and second digits of the code represent the digital states of the transmittance of 3.407THz and 5.308THz respectively; Figure 2 The terahertz transmission spectrum is obtained. In the figure, the ordinate is the transmittance, the abscissa is the frequency, and the unit is THz; the two vertical dotted lines mark the transmittance at 3.407THz of frequency A and 5.308THz of frequency B to determine the digital state encoding. If the transmittance at this frequency is greater than 50%, the digital state encoding is "1", and if the transmittance at this frequency is less than 50%, the digital state encoding is "0".

[0017] In the initial stage, the external bias voltage controls the graphene Fermi level of graphene layer 1 to 0.8 eV, and controls the graphene Fermi level of graphene layer 2 to 0.8 eV. At this time, the transmittance at 3.407 THz and 5.308 THz is less than 50%, and the corresponding digital state code is "00".

[0018] The external bias voltage is changed so that the graphene Fermi level of graphene layer 1 is 1.1eV, and the graphene Fermi level of graphene layer 2 is 0.8eV. At this time, the transmittance at 3.407THz is lower than 50%, and the transmittance at 5.308THz is higher than 50%, and the corresponding digital state code is "01".

[0019] The external bias voltage is changed so that the graphene Fermi level of graphene layer 1 is 0.8 eV, and the graphene Fermi level of graphene layer 2 is 1.1 eV. At this time, the transmittance at 3.407 THz is higher than 50%, and the transmittance at 5.308 THz is lower than 50%, and the corresponding digital state code is "10".

[0020] The external bias voltage is changed so that the Fermi level of graphene layer 1 and graphene layer 2 is 1.1eV. At this time, the transmittance at 3.407THz and 5.308THz is higher than 50%, and the corresponding digital state code is "11".

[0021] In summary, the present invention achieves the shift of the transmission trough by adjusting the Fermi level of graphene distributed in two layers, and can achieve the change of transmittance at a specific frequency by controlling the Fermi level of graphene, thereby finally achieving 2-bit encoding.

[0022] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0023] In the description of the present invention, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0024] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A 2-bit graphene encoder with a multi-layer structure, characterized in that: The encoder is a periodically arranged square structural unit; In a unit structure, it includes: a graphene layer 1, a substrate layer 1, a graphene layer 2 and a substrate layer 2; The graphene 1 layer is arranged on the upper surface of the substrate 1 layer, the substrate 1 layer is arranged on the upper surface of the graphene 2 layer, and the graphene 2 layer is arranged on the upper surface of the substrate 2 layer; the graphene 1 layer includes 4 first graphene units, and the graphene 2 layer includes 4 second graphene units; the 4 first graphene units are symmetrical about the center of the intersection of the diagonals of the device, and the 4 second graphene units are symmetrical about the center of the intersection of the diagonals of the device; the first graphene unit and the second graphene unit do not overlap in a vertical position, the second graphene unit includes a first graphene elliptical module and a second graphene elliptical module, and the second graphene elliptical module is formed by rotating the first graphene elliptical module 90 degrees along a boundary point.

2. A 2-bit graphene encoder with a multi-layer structure according to claim 1, characterized in that: The side length of the square structural unit is 8 to 15 microns; the materials of the substrate layer 1 and the substrate layer 2 are both silicon dioxide, and the thickness is the same and is 0.2 to 10 microns; the thickness of the graphene layer 1 and the graphene layer 2 is the same and is less than the thickness of the substrate layer 1 and the substrate layer 2.

3. The multi-layer 2-bit graphene encoder according to claim 1, characterized in that: The first graphene unit is a rectangle with a length of 3-4 microns and a width of 0.8-1.2 microns, and the boundary between the first graphene unit and the substrate layer 1 does not overlap; the first graphene elliptical module is a quarter of an ellipse with a major axis of 3-4 microns and a minor axis of 0.3-0.9 microns.

4. A 2-bit graphene encoder using the multilayer structure of any one of claims 1 to 3, characterized in that: The 2-bit graphene encoder with the multi-layer structure can form two transmission troughs at frequency A and frequency B, and can realize the 2-bit encoding function at the frequencies of the two transmission troughs.

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