Terahertz metamaterial biosensor

Abstract

The invention provides a terahertz metamaterial biosensor, which relates to the technical field of terahertz and is formed by splicing a plurality of sensing units. The sensing unit comprises a substrate layer and a dielectric substance layer; the dielectric substance layer is arranged on the substrate layer; the dielectric substance layer comprises 25 micro-nano units which are distributed in a 5 * 5 array; each micro-nano unit comprises a cylinder and three identical cuboids; the three cuboids are arranged on the cylinder; the heights of the cylinders of the micro-nano units in the first area are equal and defined as a first height, the heights of the cylinders of the micro-nano units in the second area are equal and defined as a second height, and the heights of the cylinders of the micro-nano units in the third area are equal and defined as a third height; the second height is greater than the third height which is greater than the first height; the first region is an inner ring of the dielectric substance layer, the second region is a middle ring of the dielectric substance layer, and the third region is an outer ring of the dielectric substance layer. The method has high robustness for structural local defects, disordered disturbance and environmental noise.

Description

Technical Field

[0001] The present invention relates to the field of terahertz technology, and in particular to a terahertz metamaterial biosensor. Background Art

[0002] Electromagnetic metamaterials are sensitive to the surrounding dielectric environment and can locally enhance electromagnetic fields, thus showing broad potential for application in sensing. Biosensors based on electromagnetic metamaterials operate by converting changes in the dielectric constant surrounding the sensor into changes in the frequency domain spectrum of the electromagnetic signal, manifesting as a shift in the resonant peak position. The shift in the resonant peak is used to infer the dielectric constant of the object being measured, and thus the concentration of the sample being measured. Because metamaterials enhance electromagnetic fields, sensors using them can significantly improve their detection sensitivity.

[0003] Terahertz (THz) electromagnetic waves refer to electromagnetic waves with a frequency of 0.1-1THz. They have the characteristics of low energy (the energy of photons with a frequency of 1THz is about 4meV) and will not cause ionization damage and changes in biological tissues. Therefore, terahertz metamaterial biosensors have the characteristics of high sensitivity, low detection limit, label-free, and non-destructive testing. They have broad application prospects in the field of detection of extremely low concentration biological samples (such as tumor markers, cytokines, etc.).

[0004] Although existing terahertz metamaterial biosensors can meet the requirements of high-sensitivity detection, they are often susceptible to defects, impurities and various interferences, resulting in inaccurate detection results. Summary of the Invention

[0005] The object of the present invention is to provide a terahertz metamaterial biosensor that is highly robust against local structural defects, disordered disturbances and environmental noise.

[0006] A terahertz metamaterial biosensor is composed of a plurality of sensing units; the sensing unit includes a substrate layer and a dielectric layer;

[0007] The dielectric layer is disposed on the substrate layer;

[0008] The dielectric layer includes 25 micro-nano units distributed in a 5×5 array; the micro-nano units include a cylinder and three identical cuboids; the three cuboids are disposed on the cylinder; the three cuboids are sequentially defined as a first cuboid, a second cuboid, and a third cuboid; the distance between the first cuboid and the second cuboid is equal to the distance between the second cuboid and the third cuboid;

[0009] The center point of the lower end surface of the second cuboid coincides with the center point of the upper end surface of the cylinder;

[0010] The heights of the cylinders of the micro-nano units located in the first area are equal and defined as a first height; the heights of the cylinders of the micro-nano units located in the second area are equal and defined as a second height; the heights of the cylinders of the micro-nano units located in the third area are equal and defined as a third height; the second height is greater than the third height, and the third height is greater than the first height;

[0011] The first region is an inner circle of the dielectric layer, the second region is a middle circle of the dielectric layer, and the third region is an outer circle of the dielectric layer.

[0012] Optionally, the first height is 38-42 μm, the second height is 58-62 μm, and the third height is 48-52 μm.

[0013] Optionally, the first height is 40 μm, the second height is 60 μm, and the third height is 50 μm.

[0014] Optionally, the diameter of the cylinder is 150 μm.

[0015] Optionally, the cuboid has a length of 90 μm, a width of 20 μm, and a height of 10 μm.

[0016] Optionally, the distance between the cylinders is 50 μm.

[0017] Optionally, the dielectric layer is made of high-resistance silicon.

[0018] The effects of the present invention are as follows:

[0019] The terahertz metamaterial biosensor of the present invention constructs a defect structure in the dielectric layer by arranging the second height greater than the third height, which in turn is greater than the first height. This excites topological zero modes localized at boundaries or interfaces. Protected by topological order, it exhibits strong robustness against local structural defects, disordered perturbations, and environmental noise. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 Schematic diagram of the dielectric layer structure of the present invention.

[0021] In the figure: 1, micro-nano unit; 2, first area; 3, second area; 4, third area; 11, cylinder; 12, first cuboid; 13, second cuboid; 14, third cuboid. DETAILED DESCRIPTION

[0022] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

[0023] The present invention provides a terahertz metamaterial biosensor, which is characterized by being composed of a plurality of sensing units spliced ​​together; the sensing unit comprises a substrate layer and a dielectric layer.

[0024] The dielectric layer is disposed on the substrate layer. Preferably, the dielectric layer is made of high-resistance silicon with a resistivity greater than 5000 Ω·cm. The substrate layer is made of silicate glass, specifically including Schott BF33, Schott BK7, and Corning 7070 glass, with a real part of the dielectric constant ε less than 3 in the 0.1-1 THz frequency band.

[0025] The dielectric layer includes 25 micro-nano units 1 arranged in a 5×5 array. The micro-nano units 1 include a cylinder 11 and three identical cuboids. The three cuboids are each disposed on the cylinder 11. The three cuboids are defined as a first cuboid 12, a second cuboid 13, and a third cuboid 14. The distance between the first cuboid 12 and the second cuboid 13 is equal to the distance between the second cuboid 13 and the third cuboid 14. Preferably, the diameter of the cylinder 11 is 150 μm. The cuboid has a length of 90 μm, a width of 20 μm, and a height of 10 μm. The distance between each cylinder 11 is 50 μm.

[0026] The center point of the lower end surface of the second cuboid 13 coincides with the center point of the upper end surface of the cylinder 11 .

[0027] The heights of the cylinders 11 of the micro-nano units 1 located in the first area 2 are equal and defined as a first height, the heights of the cylinders 11 of the micro-nano units 1 located in the second area 3 are equal and defined as a second height, and the heights of the cylinders 11 of the micro-nano units 1 located in the third area 4 are equal and defined as a third height; the second height is greater than the third height, and the third height is greater than the first height.

[0028] Specifically, the first height is 38-42 μm, preferably 40 μm; the second height is 58-62 μm, preferably 60 μm; and the third height is 48-52 μm, preferably 50 μm.

[0029] The first region 2 is the inner circle of the dielectric layer, the second region 3 is the middle circle of the dielectric layer, and the third region 4 is the outer circle of the dielectric layer.

[0030] When the substrate layer of the sensor of the present invention is deformed by ±10%, the resonance frequency fluctuation is less than 0.1%, which is much lower than that of the traditional sensor (frequency shift>8%).

[0031] The embodiments described above are merely descriptions of preferred implementations of the present invention and are not intended to limit the scope of the present invention. Without departing from the spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should fall within the scope of protection determined by the claims of the present invention.

Claims

1. A terahertz metamaterial biosensor, characterized in that: It is composed of several sensing units spliced ​​together; the sensing unit includes a substrate layer and a dielectric layer; The dielectric layer is disposed on the substrate layer; The dielectric layer includes 25 micro-nano units distributed in a 5×5 array; the micro-nano units include a cylinder and three identical cuboids; the three cuboids are disposed on the cylinder; the three cuboids are sequentially defined as a first cuboid, a second cuboid, and a third cuboid; the distance between the first cuboid and the second cuboid is equal to the distance between the second cuboid and the third cuboid; The center point of the lower end surface of the second cuboid coincides with the center point of the upper end surface of the cylinder; The heights of the cylinders of the micro-nano units located in the first area are equal and defined as a first height; the heights of the cylinders of the micro-nano units located in the second area are equal and defined as a second height; the heights of the cylinders of the micro-nano units located in the third area are equal and defined as a third height; the second height is greater than the third height, and the third height is greater than the first height; The first region is an inner circle of the dielectric layer, the second region is a middle circle of the dielectric layer, and the third region is an outer circle of the dielectric layer.

2. The terahertz metamaterial biosensor according to claim 1, characterized in that: The first height is 38-42 μm, the second height is 58-62 μm, and the third height is 48-52 μm.

3. The terahertz metamaterial biosensor according to claim 2, characterized in that: The first height is 40 μm, the second height is 60 μm, and the third height is 50 μm.

4. The terahertz metamaterial biosensor according to claim 1, characterized in that: The cylinder has a diameter of 150 μm.

5. The terahertz metamaterial biosensor according to claim 1, characterized in that: The cuboid has a length of 90 μm, a width of 20 μm, and a height of 10 μm.

6. The terahertz metamaterial biosensor according to claim 1, characterized in that: The distance between the cylinders is 50 μm.

7. The terahertz metamaterial biosensor according to claim 1, characterized in that: The dielectric layer is made of high-resistance silicon.

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