阅读说明：本技术 一种基于温度不敏感的太赫兹波超材料的生物传感装置 (Temperature-insensitive terahertz wave metamaterial-based biosensing device ) 是由 李丹 于 2020-06-24 设计创作，主要内容包括：本发明提供了一种基于温度不敏感的太赫兹波超材料的生物传感装置,包括：太赫兹源、准直系统、斩波器、迈克尔逊干涉系统、太赫兹传感系统和探测系统；其中太赫兹传感系统,具体包括自下而上依次设置的衬底层、超材料层；衬底层为0.65CaTiO<Sub>3</Sub>-0.35NdAlO<Sub>3</Sub>介电陶瓷,超材料层包括具有周期性微纳米结构的太赫兹PIT结构阵列和两个电极；太赫兹PIT结构阵列包括多个石墨烯PIT(等离子体诱导透明)单元；相邻两列石墨烯PIT单元连接到不同的电极；通过外加电压的改变,可以改变石墨烯内部载流子的浓度,可以在太赫兹传感装置中实现对生物样品的透明窗口进行动态调制。本发明的有益效果是：解决了太赫兹波单谱传感器中存在温度影响大、灵敏度低、光谱探测波长不能动态调谐等问题。(The invention provides a temperature-insensitive terahertz wave metamaterial-based biosensor device, which comprises: the terahertz detection device comprises a terahertz source, a collimation system, a chopper, a Michelson interference system, a terahertz sensing system and a detection system; the terahertz sensing system specifically comprises a substrate layer and a metamaterial layer which are sequentially arranged from bottom to top; the substrate layer is 0.65CaTiO 3 ‑0.35NdAlO 3 The dielectric ceramic, the metamaterial layer includes terahertz PIT structure array with periodic micro-nano structure and two electrodes; the terahertz PIT structure array comprises a plurality of graphene PITs (plasma PITs)Body-induced transparency) units; two adjacent columns of graphene PIT units are connected to different electrodes; through the change of the external voltage, the concentration of carriers in the graphene can be changed, and the transparent window of the biological sample can be dynamically modulated in the terahertz sensing device. The invention has the beneficial effects that: the problems that a terahertz wave single-spectrum sensor is large in temperature influence, low in sensitivity, incapable of dynamically tuning spectrum detection wavelength and the like are solved.)

1. A temperature insensitive terahertz wave metamaterial-based biosensing device is characterized in that: the method comprises the following steps: the terahertz detection device comprises a terahertz source, a collimation system, a chopper, a Michelson interference system, a terahertz sensing system and a detection system; the chopper is arranged on an optical path between the collimating system and the Michelson interference system; the terahertz sensing system comprises a substrate layer and a metamaterial layer which are sequentially arranged from bottom to top;

the substrate layer is 0.65CaTiO₃-0.35NdAlO₃The dielectric ceramic, the metamaterial layer includes terahertz PIT structure array with periodic micro-nano structure and two electrodes; the two electrodes are respectively positioned on two sides of the metamaterial layer, and a variable voltage source is connected between the two electrodes and used for providing variable voltage; coating a biological sample to be detected on the surface of the metamaterial layer;

the terahertz PIT structure array comprises a plurality of graphene PIT units; two adjacent columns of graphene PIT units are connected to different electrodes; changing the concentration of carriers in the graphene by changing the external voltage so as to realize dynamic modulation on a transparent window of a biological sample in the terahertz sensing device;

the terahertz wave generated by the terahertz source enters the chopper after being collimated by the collimating system, the received terahertz wave is periodically sent into the Michelson interference system by the chopper, interference light generated by the Michelson interference system enters a biological sample in the terahertz sensing system, an optical signal with biological sample information emitted in the terahertz sensing system is received by the detection system, and spectrum scanning of the biological sample is achieved.

2. The biosensor device according to claim 1, wherein the temperature-insensitive terahertz wave metamaterial comprises: each graphene PIT unit comprises five graphene rods, namely a first graphene rod, a second graphene rod, a third graphene rod, a fourth graphene rod and a fifth graphene rod;

the second graphene rod, the third graphene rod, the fourth graphene rod and the fifth graphene rod form an unconnected rectangular structure: the second graphene rod and the third graphene rod are two long sides of a rectangular structure, the fourth graphene rod and the fifth graphene rod are two short sides of the rectangular structure, and the second graphene rod and the third graphene rod are not connected with the fourth graphene rod and the fifth graphene rod, so that near-field coupling among the second graphene rod, the third graphene rod, the fourth graphene rod and the fifth graphene rod is realized;

the distance between one end of the second graphene rod and the fourth graphene rod and the distance between one end of the fifth graphene rod are d1, and the distance between the other end of the third graphene rod and the fourth graphene rod and the distance between the other end of the fifth graphene rod are d 2; the first graphene rod is perpendicular to the fourth graphene rod and the fifth graphene rod, passes through the middle points of the fourth graphene rod and the fifth graphene rod, and is connected with the fourth graphene rod and the fifth graphene rod; wherein d1 and d2 are preset values, and d1 is d 2.

3. The biosensor device according to claim 2, wherein the temperature-insensitive terahertz wave metamaterial comprises: the first graphene rods of the graphene PIT units in the same column are connected in series and then connected to an electrode at one end.

4. The biosensor device according to claim 2, wherein the temperature-insensitive terahertz wave metamaterial comprises: the length a and the width b of each graphene PIT unit are respectively 100 micrometers and 110 micrometers; the thickness of the graphene is 0.2 mu m, and the rod widths w of the first graphene rod to the fifth graphene rod are all 10 mu m; the rod length c of the fourth and fifth graphene rods is 50 μm, and the rod length d of the second and third graphene rods is 90 μm.

5. The biosensor device according to claim 1, wherein the temperature-insensitive terahertz wave metamaterial comprises:

the terahertz source is a medium-pressure mercury lamp, and the frequency range is 0.05THz-20 THz;

the collimation system comprises a first parabolic mirror OAP1 and a second parabolic mirror OAP2 which are oppositely arranged;

the michelson interference system comprises: the terahertz scanning device comprises a chopper, a beam splitter, an electric control one-dimensional translation table for scanning, a terahertz scanning reflector M1 and a fixed reflector M2, wherein the terahertz scanning reflector M1 is positioned on the electric control one-dimensional translation table;

the detection system comprises a third parabolic mirror OAP3, a Golay detector and a lock-in amplifier;

the chopper is arranged on a light path between the second parabolic mirror OAP2 and the beam splitter, the chopper, the beam splitter and the fixed reflector M2 are sequentially arranged on the same light path, the terahertz scanning reflector M1 is arranged on a reflection light path of the beam splitter, and the electrically controlled one-dimensional translation table vertically moves up and down to drive the terahertz scanning reflector M1 to vertically move up and down to change the light path between two paths of terahertz waves; the detection system is arranged on the other side of the terahertz scanning reflector M1 opposite to the beam splitter, and the third parabolic mirror OAP3, the terahertz scanning reflector M1 and the beam splitter are arranged on the same light path; and a reference signal channel of the phase-locked amplifier is connected with a signal with the same frequency and phase as the chopper, and a measurement signal channel of the phase-locked amplifier is connected with the output end of the detector and is used for amplifying a weak electric signal output by the detector.

6. The biosensor device according to claim 5, wherein the temperature-insensitive terahertz wave metamaterial comprises: terahertz waves generated by the medium-pressure mercury lamp are collimated by a first parabolic mirror OAP1 and a second parabolic mirror OAP2 and then are emitted into a chopper; the chopper periodically sends the received terahertz waves to the beam splitter; the beam splitter divides incident terahertz waves into two paths of scanning light and fixed light, the scanning light and the fixed light reflected by the fixed reflector M2 form interference light in the beam splitter after being reflected by the terahertz scanning reflector M1, the interference light is incident into a biological sample on the terahertz sensing system, an optical signal which carries biological sample information and is emitted by the terahertz sensing system is incident into a Golay detector through a third parabolic mirror OAP3, a detection signal output by the Golay detector is transmitted to a phase-locked amplifier, and the phase-locked amplifier performs phase-locked amplification on the received detection signal to generate an output signal.

7. The biosensor device according to claim 5, wherein the temperature-insensitive terahertz wave metamaterial comprises: the terahertz scanning reflecting mirror M1 and the fixed reflecting mirror M2 are both gold-plated high-reflectivity mirrors.

8. The biosensor device according to claim 1, wherein the temperature-insensitive terahertz wave metamaterial comprises: the temperature-insensitive terahertz wave metamaterial-based biosensor device further comprises an aperture diaphragm which controls the size of a light spot entering the interferometer and increases interference contrast; the aperture diaphragm is arranged between the collimation system and the chopper and used for shielding uneven components around the terahertz wave beam and realizing the uniform shaping of the terahertz wave beam.

9. The biosensor device according to claim 5, wherein the temperature-insensitive terahertz wave metamaterial comprises: the electric control one-dimensional translation table is driven by a servo motor.

10. The biosensor device according to claim 9, wherein the temperature-insensitive terahertz wave metamaterial comprises: the temperature-insensitive terahertz wave metamaterial-based biosensor device further comprises a controller and a computer; the controller is respectively electrically connected with the servo motor and the computer, and the computer controls the electric control one-dimensional translation table to vertically move up and down through the controller; the computer is also connected with the phase-locked amplifier, receives the output signal of the phase-locked amplifier, realizes the scanning of the tested biological sample, and completes the spectral analysis of the biological sample on the computer.

Technical Field

The invention relates to the field of biological detection, in particular to a temperature-insensitive terahertz wave metamaterial-based biological sensing device.

Background

With the development of terahertz radiation generation and detection technology, the application of terahertz waves in sensing and detection has attracted great attention. The terahertz sensor is widely applied to a plurality of fields such as airport security inspection systems, material detection, space signal detection, aerospace, industrial and agricultural production and the like. Due to the fact that a terahertz PIT (plasma induced transparency) structure has a narrow bandwidth and a high Q value, the terahertz wave sensor based on the metamaterial has the advantages of being small in size, high in resonance characteristic and sensitivity and easy to adjust, and is actually and widely researched.

However, in practical applications, the operating temperature of the device and the dielectric properties of the substrate material have a large effect on the modulation characteristics of the modulator.

Disclosure of Invention

In order to solve the problems, the invention provides a temperature-insensitive terahertz wave metamaterial-based biosensing device based on 0.65CaTiO_3-0.35NdAlO₃The terahertz biological tissue sensing device with the temperature coefficient close to zero resonance frequency is obtained by researching the terahertz metamaterial of the ceramic, which works in the terahertz waveband. The terahertz wave single-spectrum sensor aims to solve the technical problems that an existing terahertz wave single-spectrum sensor is large in temperature influence, low in sensitivity, incapable of dynamically tuning spectrum detection wavelength and the like. In addition, the graphene is a monomolecular layer and can generate strong mutual coupling effect with biomolecules adhered to the surface of the graphene, and the graphene metamaterial is directly connected with a biosensing device, so that the transparent window of the terahertz PIT can be dynamically adjustable by means of an external voltage, and the graphene plasma induced transparent structure has a large application space in label-free biosensing.

A temperature-insensitive terahertz wave metamaterial-based biosensing device, comprising: the terahertz detection device comprises a terahertz source, a collimation system, a chopper, a Michelson interference system, a terahertz sensing system and a detection system; the chopper is arranged on an optical path between the collimating system and the Michelson interference system;

the terahertz sensing system comprises a substrate layer and a metamaterial layer which are sequentially arranged from bottom to top(ii) a Wherein the substrate layer is 0.65CaTiO₃-0.35NdAlO₃The dielectric ceramic, the metamaterial layer includes terahertz PIT structure array with periodic micro-nano structure and two electrodes; the two electrodes are respectively positioned on two sides of the metamaterial layer, and a variable voltage source is connected between the two electrodes and used for providing voltage;

the terahertz PIT structure array comprises a plurality of graphene PIT units; two adjacent columns of graphene PIT units are connected to different electrodes; by changing the external voltage, the concentration of carriers in the graphene can be changed, so that the transparent window of the biological sample can be dynamically modulated in the terahertz sensing device;

the terahertz wave generated by the terahertz source enters the chopper after being collimated by the collimating system, the received terahertz wave is periodically sent into the Michelson interference system by the chopper, interference light generated by the Michelson interference system enters a biological sample in the terahertz sensing system, an optical signal with biological sample information emitted in the terahertz sensing system is received by the detection system, and spectrum scanning of the biological sample is achieved.

Further, each graphene PIT unit comprises five graphene rods, namely a first graphene rod, a second graphene rod, a third graphene rod, a fourth graphene rod and a fifth graphene rod;

the second graphene rod, the third graphene rod, the fourth graphene rod and the fifth graphene rod form an unconnected rectangular structure: the second graphene rod and the third graphene rod are two long sides of a rectangular structure, the fourth graphene rod and the fifth graphene rod are two short sides of the rectangular structure, and the second graphene rod and the third graphene rod are not connected with the fourth graphene rod and the fifth graphene rod, so that near-field coupling among the second graphene rod, the third graphene rod, the fourth graphene rod and the fifth graphene rod is realized;

the distance between one end of the second graphene rod and the fourth graphene rod and the distance between one end of the fifth graphene rod are d1, and the distance between the other end of the third graphene rod and the fourth graphene rod and the distance between the other end of the fifth graphene rod are d 2; the first graphene rod is perpendicular to the fourth graphene rod and the fifth graphene rod, passes through the middle points of the fourth graphene rod and the fifth graphene rod, and is connected with the fourth graphene rod and the fifth graphene rod; d1 and d2 are preset values, and d1 is d 2;

the first graphene rods of the graphene PIT units in the same column are connected in series and then connected to an electrode at one end.

Further, the length a and the width b of each graphene PIT unit are 100 μm and 110 μm, respectively; the thickness of the graphene is 0.2 mu m, and the rod widths w of the first graphene rod to the fifth graphene rod are all 10 mu m; the rod length c of the fourth and fifth graphene rods is 50 μm, and the rod length d of the second and third graphene rods is 90 μm.

Further, the terahertz source is a medium-pressure mercury lamp (frequency: 0.05THz-20 THz);

the collimation system comprises a first parabolic mirror OAP1 and a second parabolic mirror OAP2 which are oppositely arranged;

the michelson interference system comprises: the terahertz scanning device comprises a chopper, a beam splitter, an electric control one-dimensional translation table for scanning, a terahertz scanning reflector M1 and a fixed reflector M2, wherein the terahertz scanning reflector M1 is positioned on the electric control one-dimensional translation table;

the detection system comprises a third parabolic mirror OAP3, a Golay detector and a lock-in amplifier;

the chopper is arranged on a light path between the second parabolic mirror OAP2 and the beam splitter, the chopper, the beam splitter and the fixed reflector M2 are sequentially arranged on the same light path, the terahertz scanning reflector M1 is arranged on a reflection light path of the beam splitter, and the electrically controlled one-dimensional translation table can vertically move up and down to drive the terahertz scanning reflector M1 to vertically move up and down to change the light path between two paths of terahertz waves; the detection system is arranged on the other side of the terahertz scanning reflector M1 opposite to the beam splitter, and the third parabolic mirror OAP3, the terahertz scanning reflector M1 and the beam splitter are arranged on the same light path; the reference signal channel of the phase-locked amplifier is connected with a signal with the same frequency and phase as the chopper, and the measurement signal channel of the phase-locked amplifier is connected with the output end of the detector and used for amplifying a weak electric signal output by the detector;

terahertz waves generated by the medium-pressure mercury lamp are collimated by a first parabolic mirror OAP1 and a second parabolic mirror OAP2 and then are emitted into a chopper; the chopper periodically sends the received terahertz waves to the beam splitter; the beam splitter divides incident terahertz waves into two paths of scanning light and fixed light, the scanning light and the fixed light reflected by the fixed reflector M2 form interference light in the beam splitter after being reflected by the terahertz scanning reflector M1, the interference light is incident into a biological sample on the terahertz sensing system, an optical signal which carries biological sample information and is emitted by the terahertz sensing system is incident into a Golay detector through a third parabolic mirror OAP3, a detection signal output by the Golay detector is transmitted to a phase-locked amplifier, and the phase-locked amplifier performs phase-locked amplification on the received detection signal to generate an output signal.

Further, the terahertz scanning mirror M1 and the fixed mirror M2 are both gold-plated high-reflectivity mirrors.

Further, the temperature-insensitive terahertz wave metamaterial-based biosensor device further comprises an aperture diaphragm which controls the size of a light spot entering the interferometer and increases interference contrast; the aperture diaphragm is arranged between the collimation system and the chopper and used for shielding uneven components around the terahertz wave beam and realizing the uniform shaping of the terahertz wave beam.

Further, the electric control one-dimensional translation table is driven by a servo motor.

Further, the temperature-insensitive terahertz wave metamaterial-based biosensor device further comprises a controller and a computer; the controller is respectively electrically connected with the servo motor and the computer, and the computer controls the electric control one-dimensional translation table to vertically move up and down through the controller; the computer is also connected with the phase-locked amplifier, receives the output signal of the phase-locked amplifier, realizes the scanning of the tested biological sample, and completes the spectral analysis of the biological sample on the computer.

The technical scheme provided by the invention has the beneficial effects that: the invention provides a biological sensing device based on a temperature-insensitive terahertz wave metamaterial by combining a terahertz technology with a PIT metamaterial structure.

The substrate layer of the terahertz sensing system has low dielectric loss and high quality factorAnd near-zero temperature coefficient of 0.65CaTiO₃-0.35NdAlO₃The dielectric ceramic, the metamaterial layer is a terahertz PIT (plasma induced transparent) structure array with a periodic micro-nano structure; through the change of voltage, the concentration of carriers in the graphene can be changed, and therefore dynamic modulation of a transparent window in a transmission spectrum can be achieved.

The PIT structure has a narrow bandwidth and a high Q value, and therefore has high sensitivity to label-free biosensing. In addition, the graphene is a monomolecular layer and can generate strong mutual coupling effect with biomolecules adhered to the surface of the monomolecular layer, so that the graphene plasma induced transparent structure has a large development space on label-free biosensing. Because the electrode is directly connected with the sensor, the transparent window and the resonance peaks at two ends of the electrode can be dynamically adjusted, and the application of the electrode in biosensing is further expanded.

Drawings

The invention will be further described with reference to the accompanying drawings and examples, in which:

FIG. 1 is an apparatus diagram of a temperature insensitive terahertz wave metamaterial-based biosensor in an embodiment of the present invention;

FIG. 2 is a cross-sectional view of a terahertz sensing system in an embodiment of the invention;

FIG. 3 is a top view of a terahertz sensing system in an embodiment of the invention;

fig. 4 is a schematic structural diagram of each graphene PIT unit in an embodiment of the present invention; wherein, a is 100 μm, b is 110 μm, c is 50 μm, d is 80 μm, w is 10 μm, and s is 3 μm;

fig. 5 is a three-dimensional schematic diagram of a terahertz sensing system in an embodiment of the present invention.

Detailed Description

For a more clear understanding of the technical features, objects and effects of the present invention, embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

The embodiment of the invention provides a temperature-insensitive terahertz wave metamaterial-based biosensing device.

Referring to fig. 1, fig. 1 is a diagram illustrating a temperature insensitive terahertz metamaterial-based biosensor device according to an embodiment of the present invention; the method comprises the following steps:

the terahertz detection device comprises a terahertz source, a collimation system, a chopper 4, a Michelson interference system, a terahertz sensing system 12 and a detection system; the chopper 4 is arranged on a light path between the collimation system and the Michelson interference system and is used for carrying out periodic modulation on THz waves emitted by the high-stability medium-pressure mercury lamp so as to be detected by a Golay detector;

the terahertz wave generated by the terahertz source enters the chopper 4 after being collimated by the collimating system, the received terahertz wave is periodically sent to the Michelson interference system by the chopper 4, interference light generated by the Michelson interference system is incident into a biological sample in the terahertz sensing system 12, an optical signal with biological sample information emitted in the terahertz sensing system 12 is received by the detection system, and the spectral scanning of the biological sample is realized;

referring to fig. 2, fig. 2 is a cross-sectional view of a terahertz sensing system in an embodiment of the present invention; the terahertz sensing system 12 comprises a substrate layer 122 and a metamaterial layer 121 which are sequentially arranged from bottom to top; wherein the substrate layer 122 is 0.65CaTiO with low dielectric loss, high quality factor and near-zero temperature coefficient₃-0.35NdAlO₃The metamaterial layer 121 comprises a terahertz PIT (plasma induced transparent) structure array with a periodic micro-nano structure; coating a biological sample to be detected on the surface of the metamaterial layer;

referring to fig. 3, fig. 3 is a top view of a terahertz sensing system according to an embodiment of the present invention, where the terahertz PIT structure array includes a plurality of graphene PIT units 1211; the number of the graphene PIT units 1211 is determined according to the size of the biological sample 13 to be detected, and the larger the number of rows and columns of the graphene PIT units 1211 is, the larger the size of the corresponding metamaterial layer 121 is.

Referring to fig. 4, fig. 4 is a schematic structural diagram of each graphene PIT unit in the embodiment of the present invention; each graphene PIT unit 1211 includes five graphene rods, respectively a first graphene rod 12111, a second graphene rod 12112, a third graphene rod 12113, a fourth graphene rod 12114, and a fifth graphene rod 12115; wherein the second graphene rod 12112, the third graphene rod 12113, the fourth graphene rod 12114 and the fifth graphene rod 12115 constitute rectangular structures that are not connected to each other: the second graphene rod 12112 and the third graphene rod 12113 are two long sides of a rectangular structure, the fourth graphene rod 12114 and the fifth graphene rod 12115 are two short sides of the rectangular structure, and the second graphene rod 12112 and the third graphene rod 12113 are not connected to the fourth graphene rod 12114 and the fifth graphene rod 12115, so as to realize near-field coupling between the second graphene rod 12112 and the third graphene rod 12113 and between the fourth graphene rod 12114 and the fifth graphene rod 12115;

a distance between the second graphene rod 12112 and one ends of the fourth and fifth graphene rods 12114 and 12115 is d1, a distance between the third and fourth graphene rods 12114 and 12115 is d2, and d1 ═ d2 ═ 3 μm; the first graphene rod 12111 is disposed perpendicular to the fourth graphene rod 12114 and the fifth graphene rod 12115, passes through the midpoint of the fourth graphene rod 12114 and the fifth graphene rod 12115, and is connected to the fourth graphene rod 12114 and the fifth graphene rod 12114;

the length a and the width b of each graphene PIT unit 1211 are 100 μm and 110 μm, respectively; the thickness of the graphene is 0.2 μm, and the bar widths w of the first graphene bar 12111 to the fifth graphene bar 12115 are all 10 μm; the rod length c of the fourth and fifth graphene rods 12114 and 12115 is 50 μm, and the rod length d of the second and third graphene rods 12112 and 12113 is 90 μm.

The metamaterial layer 121 further includes two electrodes (1212 and 1213); the two electrodes are respectively located at two sides of the metamaterial layer 121, and a variable voltage source 1214 is connected between the two electrodes for providing voltage; the voltage range of the voltage source 1214 is between several volts and dozens of volts, in the embodiment of the present invention, the voltage range of the voltage source 1214 is between 5V and 90V;

the first graphene rods 12111 of the graphene PIT units 1211 in the same row are connected in series and then connected to an electrode at one end, and the graphene PIT units 1211 in two adjacent rows are connected to different electrodes.

Referring to fig. 5, fig. 5 is a three-dimensional schematic diagram of a terahertz sensing system according to an embodiment of the present invention; for ease of viewing, fig. 5 is a side-on three-dimensional schematic view for ease of viewing the particular structure of the layer of superconducting material 121; through the change of the external voltage of the graphene, the concentration of carriers in the graphene can be changed, so that the transparent window of the biological sample can be dynamically modulated in the terahertz sensing device.

The 0.65CaTiO₃-0.35NdAlO₃The preparation method of the dielectric ceramic comprises the following steps: research on dry pressing pressure, sintering temperature and time of powder to 0.65CaTiO by using solid-phase reaction method system₃-0.35NdAlO₃The influence of the phase structure and the dielectric property of the ceramic is that the ceramic is sintered for 6 hours at 1420 ℃ to prepare compact 0.65CaTiO with the temperature coefficient of near-zero resonance frequency₃-0.35NdAlO₃A ceramic.

Preparing graphene by a Chemical Vapor Deposition (CVD) method, and transferring the graphene to the prepared 0.65CaTiO₃-0.35NdAlO₃And then, according to PIT size parameters obtained by finite element simulation results, the trial production of the terahertz wave modulator is completed by utilizing an oxygen plasma etching technology on the dielectric ceramic substrate.

The terahertz source is a broadband (frequency: 0.05THz-20THz) terahertz source and is used for providing broadband terahertz waves. In the embodiment of the invention, the terahertz source is a high-stability medium-pressure mercury lamp 1 for generating a THz light source;

the collimation system comprises a first parabolic mirror (OAP1)2 and a second parabolic mirror (OAP2)3 which are oppositely arranged;

the michelson interference system comprises: the terahertz scanning mirror comprises a beam splitter 11, an electronic control one-dimensional translation table 5, a terahertz scanning mirror (M1)6 and a fixed mirror (M2), wherein the beam splitter is manufactured by a metal grating manufacturing process on a Mylar film, and the transmission reflectance of the beam splitter is close to 1: 1;

the detection system comprises a third parabolic mirror (OAP3)8, a Golay detector 9 for collecting interference light, and a phase-locked amplifier 10 for performing phase-locked amplification processing on a detection signal output by the Golay detector;

the chopper 4 is arranged on a light path between the second parabolic mirror (OAP2)3 and the beam splitter 11, the chopper 4, the beam splitter 11 and the fixed reflector (M2)7 are sequentially arranged on the same light path, the terahertz scanning reflector (M1)6 is arranged on a reflection light path of the beam splitter 11, the electrically controlled one-dimensional translation stage 5 can vertically move up and down to drive the terahertz scanning reflector (M1)6 to vertically move up and down to change the light path between two paths of terahertz waves; the detection system is arranged on the other side of the terahertz scanning mirror (M1)6 relative to the beam splitter 11, and the third parabolic mirror (OAP3)8, the terahertz scanning mirror (M1)6 and the beam splitter 11 are arranged on the same light path; the reference signal channel of the phase-locked amplifier 10 is connected with a signal with the same frequency and phase as the chopper 4, and the measurement signal channel of the phase-locked amplifier is connected with the output end of the detector 9 and is used for amplifying a weak electric signal output by the detector 9.

The terahertz wave generated by the medium-pressure mercury lamp 1 is collimated by a first parabolic mirror (OAP1)2 and a second parabolic mirror (OAP2)3 and then is absorbed into a chopper 4; the chopper 4 periodically sends the received terahertz waves to the beam splitter 11; the beam splitter 11 splits incident terahertz waves into two paths of scanning light and fixed light, the scanning light forms interference light with the fixed light reflected by the fixed reflector (M2)7 in the beam splitter 11 after being reflected by the terahertz scanning reflector (M1)6, the interference light is incident into a biological sample 13 on the terahertz sensing system 12, an optical signal which carries biological sample information and is emitted by the terahertz sensing system 12 is emitted into the Golay detector 9 through the third parabolic mirror (OAP3)8, a detection signal output by the Golay detector 9 is transmitted to the lock-in amplifier 10, and the lock-in amplifier 10 performs lock-in amplification processing on the received detection signal to generate an output signal.

The first parabolic mirror (OAP1)2, the second parabolic mirror (OAP2)3 and the third parabolic mirror (OAP3)8 are all gold-plated off-axis parabolic mirrors for collimation. The terahertz scanning reflector (M1)6 and the fixed reflector (M2)7 are both gold-plated high-reflectivity mirrors.

The temperature-insensitive terahertz wave metamaterial-based biosensor device further comprises an aperture diaphragm 14 for controlling the size of a light spot entering the interferometer and increasing the interference contrast; the aperture diaphragm 14 is arranged between the collimation system and the chopper 4 and used for shielding uneven components around the terahertz wave beam and realizing the uniform shaping of the terahertz wave beam.

The electrically controlled one-dimensional translation stage 5 is driven by a servo motor 15, and a computer is connected with a stepping motor controller through an interface component and is used for realizing the operation of the stepping motor controller; the stepping motor controller controls the action of the servo motor to realize the one-dimensional movement of the scanning reflector (M1), so that the optical path between two paths of terahertz wave beams (reflected light and fixed light) is changed, and the spectrum scanning of the tested biological sample 13 is realized.

The temperature-insensitive terahertz wave metamaterial-based biosensor device further comprises a controller 16 and a computer 17; the controller 16 is respectively electrically connected with the servo motor 15 and the computer 17, and the computer 17 controls the electric control one-dimensional translation table 5 to vertically move up and down through the controller 16; the computer 17 is also electrically connected with the lock-in amplifier 10, receives the output signal of the lock-in amplifier 10, realizes the scanning of the tested biological sample 13, and completes the spectral analysis of the biological sample 13 on the computer 17.

The invention has the beneficial effects that: the invention provides a biological sensing device based on a temperature-insensitive terahertz wave metamaterial by combining a terahertz technology with a PIT metamaterial structure.

The substrate layer of the terahertz sensing system is 0.65CaTiO with low dielectric loss, high quality factor and near-zero temperature coefficient₃-0.35NdAlO₃The dielectric ceramic, the metamaterial layer is a terahertz PIT (plasma induced transparent) structure array with a periodic micro-nano structure; through the change of voltage, the concentration of carriers in the graphene can be changed, and therefore dynamic modulation of a transparent window in a transmission spectrum can be achieved.

The PIT structure has a narrow bandwidth and a high Q value, and therefore has high sensitivity to label-free biosensing. In addition, the graphene is a monomolecular layer and can generate strong mutual coupling effect with biomolecules adhered to the surface of the monomolecular layer, so that the graphene plasma induced transparent structure has a large development space on label-free biosensing. Because the electrode is directly connected with the sensor, the transparent window and the resonance peaks at two ends of the electrode can be dynamically adjusted, and the application of the electrode in biosensing is further expanded.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.