A terahertz wave band magnetic field and temperature sensor based on SPR-MOF

Abstract

The application discloses a terahertz wave band magnetic field and temperature sensor based on SPR-MOF. The sensor is based on a microstructure optical fiber made of cycloolefin polymer Zeonex, and the base material is provided with a cladding layer and a core. The cladding layer is arranged with two layers of cladding small air holes in a regular hexagonal lattice structure, and an amplification air hole is arranged on each side of the core. Plane polishing surfaces are arranged on the upper side and the lower side of the base material, and MoS2 films are deposited on the two plane polishing surfaces. The MoS2 film on the upper polishing surface covers a magnetic field sensitive material, and the MoS2 film on the lower polishing surface covers a temperature sensitive material. The two independent surface plasmon resonance excitation channels can simultaneously measure the magnetic field and the temperature in the terahertz wave band, and the structure is simple and high in sensitivity, and is suitable for multifunctional sensing in a complex environment.

Description

Technical Field

[0001] This invention belongs to the field of terahertz fiber optic sensing application technology, and relates to a terahertz band magnetic field and temperature sensor based on SPR-MOF. Background Technology

[0002] Magnetic field detection has important applications in industrial automation, biomedical diagnostics, and geological exploration. However, high-sensitivity magnetic field sensors generally face the problem of temperature cross-sensitivity in practical use; even small fluctuations in ambient temperature can significantly interfere with the accuracy of magnetic field measurements. Therefore, developing dual-parameter sensors capable of simultaneously detecting magnetic fields and temperature, improving the reliability of magnetic field measurements through real-time temperature compensation, and achieving multifunctional integrated sensing in complex environments has become an important direction in the development of current sensing technology.

[0003] Among numerous sensing technologies, surface plasmon resonance (SPR) technology has attracted widespread attention due to its extreme sensitivity to changes in the refractive index of the environment at the metal-dielectric interface. Meanwhile, microstructured optical fibers (MOFs), with their extremely high degree of freedom in structural design, cutoff-free single-mode transmission characteristics, and unique microporous structure, provide an ideal waveguide platform for the strong interaction between light and matter. The SPR-MOF sensor, constructed by deeply integrating these two technologies, cleverly combines the miniaturization and electromagnetic interference resistance advantages of fiber optic devices with the ultra-high sensitivity of SPR technology. By selectively coating SPR-excited metal thin films on the inside of the fiber pores or polished surfaces and filling them with different sensitive media, simultaneous multi-channel detection can be achieved. Currently, based on this approach, various dual-parameter detection schemes for magnetic fields and temperature have been successfully proposed in the visible and near-infrared bands, and significant progress has been made in both theoretical and experimental aspects.

[0004] In contrast, the terahertz band has unique advantages in magnetic field detection. Terahertz photons have low energy and strong penetrating power, which can more effectively excite the magnetic dipole moment of magnetically responsive materials, thus achieving higher magnetic field sensitivity. However, most existing magnetic field and temperature sensors in the terahertz band adopt structures such as fiber gratings or SPR metasurfaces, and the gain effect brought about by combining SPR technology with microstructured optical fibers has not been fully explored. Furthermore, they still face the common problem of cross-sensitivity to temperature. Therefore, developing a dual-parameter sensor based on an SPR-MOF structure that can simultaneously detect magnetic fields and temperatures in the terahertz band has significant research value and application prospects. Summary of the Invention

[0005] To address the aforementioned technical problems and deficiencies, this invention provides a terahertz band magnetic field and temperature sensor based on SPR-MOF.

[0006] In a first aspect, the present invention provides a terahertz magnetic field and temperature sensor based on SPR-MOF, comprising: a microstructured optical fiber composed of a cyclic olefin polymer Zeonex as the substrate material.

[0007] The substrate material consists of a fiber core and a cladding. The cladding has two layers of circular air holes arranged in a regular hexagonal lattice, serving as small air holes in the cladding. The fiber core is located in the central region of the substrate material, and a circular air hole is provided on each side of the fiber core, serving as enlarged air holes. The upper and lower sides of the substrate material are respectively provided with planar polished surfaces, serving as the upper polished surface and the lower polished surface; MoS2 thin films are respectively disposed on the upper polished surface and the lower polished surface, serving as the upper excitation layer and the lower excitation layer; The surface of the upper excitation layer is provided with a magnetic field sensitive material, and the surface of the lower excitation layer is provided with a temperature sensitive material.

[0008] Furthermore, in the SPR-MOF-based terahertz magnetic field and temperature sensor provided by the present invention, the magnetic field sensitive material is a water-based triferromagnetic fluid. The temperature-sensitive material is polydimethylsiloxane.

[0009] Furthermore, in the SPR-MOF-based terahertz magnetic field and temperature sensor provided by this invention, the volume concentration of the water-based ferromagnetic fluid is 1.5%~1.8%.

[0010] Furthermore, in the SPR-MOF-based terahertz magnetic field and temperature sensor provided by the present invention, the radius of the cladding small air hole is 66~74 μm, and the spacing between adjacent cladding small air holes is 240~260 μm.

[0011] Furthermore, in the SPR-MOF-based terahertz magnetic field and temperature sensor provided by this invention, the radius of the enlarged pore is 86~94 μm.

[0012] Furthermore, in the SPR-MOF-based terahertz magnetic field and temperature sensor provided by the present invention, the polishing depth of the upper polishing surface and the lower polishing surface is 290~310 μm.

[0013] Furthermore, in the SPR-MOF-based terahertz magnetic field and temperature sensor provided by the present invention, the thickness of the MoS2 thin film is 7.6~8.4 μm.

[0014] Furthermore, in the SPR-MOF-based terahertz magnetic field and temperature sensor provided by the present invention, the magnetic field detection range of the sensor is 0~500 Oe, and the temperature detection range is 20~50℃.

[0015] Furthermore, in the SPR-MOF-based terahertz magnetic field and temperature sensor provided by the present invention, the magnetic field detection sensitivity of the sensor is 0.226 μm / Oe, and the temperature detection sensitivity is 0.1 μm / ℃.

[0016] Compared with the prior art, the technical solution provided by the present invention has at least the following beneficial effects or advantages: (1) This invention prepares MoS2 thin films on the upper and lower polished surfaces of a microstructured optical fiber, forming an upper excitation layer and a lower excitation layer, respectively. A magnetic field-sensitive material (upper sensing channel) is placed on the surface of the upper excitation layer, and a temperature-sensitive material (lower sensing channel) is placed on the surface of the lower excitation layer, thereby constructing two spectrally independent and non-overlapping resonance peaks. The magnetic field-sensitive material in the upper sensing channel primarily responds to changes in the magnetic field and has only a weak response to changes in temperature; the temperature-sensitive material in the lower sensing channel primarily responds to changes in temperature. By decoupling the differential response characteristics of the magnetic field and temperature using the two resonance peaks, the values ​​of the magnetic field and temperature can be extracted simultaneously and accurately, effectively eliminating the cross-sensitivity interference of ambient temperature on magnetic field measurement and significantly improving the reliability and accuracy of magnetic field detection.

[0017] (2) This invention deeply integrates surface plasmon resonance (SPR) technology with a microstructured optical fiber (MOF) platform, fully leveraging the unique advantages of terahertz wave photons—low energy, strong penetration, and the ability to effectively excite the magnetic dipole moment of magnetically responsive materials. By systematically optimizing key structural parameters such as the radius of small air holes in the cladding, enlarging the air hole radius, the spacing between small air holes in the cladding, the polishing depth, and the thickness of the MoS2 film, the core mode and the surface plasmon resonance (SPP) mode achieve optimal phase matching conditions, resulting in sharp waveforms and high quality factors for both resonance peaks. Experimental results show that within the magnetic field range of 0–500 Oe and the temperature range of 20–50 °C, the sensor achieves a maximum magnetic field sensitivity of 0.226 μm / Oe and a maximum temperature sensitivity of 0.1 μm / °C, realizing high-precision simultaneous detection of dual parameters.

[0018] (3) Based on the extremely high degree of structural design freedom of microstructured optical fibers, this invention achieves effective control of optical fiber structure dispersion by rationally designing the arrangement of small air holes in the cladding and enlarging the size of the air holes. The wavelength variation windows of the two resonance peaks are separated from each other and do not overlap throughout the entire test range. The magnetic field sensing channel and the temperature sensing channel have extremely low cross sensitivity, thereby ensuring the reliability and stability of simultaneous detection of two parameters under complex environments.

[0019] (4) This invention overcomes the limitations of existing terahertz band sensors, which mostly employ fiber gratings or SPR metasurface structures, and provides a new technical solution for the deep integration of SPR technology and microstructured optical fibers in the terahertz band, filling a technological gap in this field. Furthermore, this high-performance dual-parameter detection capability has significant practical value and broad application prospects in sensing applications under complex environments such as biomedical diagnostics, high-precision industrial monitoring, and geological exploration. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the cross-sectional structure of the sensor. In the diagram, 1 is the cladding small air hole, 2 is the enlarged air hole, 3 is the upper excitation layer, 4 is the lower excitation layer, 5 is the magnetic field sensitive material, 6 is the temperature sensitive material, and 7 is the substrate material.

[0021] Figure 2 This is a schematic diagram of the sensor's three-dimensional structure.

[0022] Figure 3 The graph shows the relationship between the resonant loss curve of the sensor and the real part of the effective refractive index in the core mode as a function of wavelength under the conditions of an applied magnetic field of 200 Oe and an ambient temperature of 20 ℃.

[0023] Figure 4 The influence of the cladding small air hole radius on the sensor loss spectrum and sensing performance is shown. Among them, (A) shows the correspondence between the cladding small air hole radius and the resonant wavelength under different applied magnetic fields; (B) shows the fitting curve of the sensor loss spectrum and the resonant wavelength under different applied magnetic fields; (C) shows the correspondence between the cladding small air hole radius and the resonant wavelength under different ambient temperatures; and (D) shows the fitting curve of the sensor loss spectrum and the resonant wavelength under different ambient temperatures.

[0024] Figure 5 The effect of enlarging the pore radius on the sensor loss spectrum and sensing performance is shown. Among them, (A) shows the correspondence between the enlarged pore radius and the resonant wavelength under different applied magnetic fields; (B) shows the fitting curves of the sensor loss spectrum and the resonant wavelength under different applied magnetic fields; (C) shows the correspondence between the enlarged pore radius and the resonant wavelength under different ambient temperatures; and (D) shows the fitting curves of the sensor loss spectrum and the resonant wavelength under different ambient temperatures.

[0025] Figure 6 The effect of the spacing between small air holes in the cladding on the sensor's loss spectrum and sensing performance is shown. Among them, (A) shows the relationship between the spacing between small air holes in the cladding and the resonant wavelength under different applied magnetic fields; (B) shows the fitting curves of the sensor's loss spectrum and the resonant wavelength under different applied magnetic fields; (C) shows the relationship between the spacing between small air holes in the cladding and the resonant wavelength under different ambient temperatures; and (D) shows the fitting curves of the sensor's loss spectrum and the resonant wavelength under different ambient temperatures.

[0026] Figure 7 The effect of polishing depth on sensor loss spectrum and sensing performance is shown. Among them, (A) shows the relationship between polishing depth and resonant wavelength under different applied magnetic fields; (B) shows the fitting curves of sensor loss spectrum and resonant wavelength under different applied magnetic fields; (C) shows the relationship between polishing depth and resonant wavelength under different ambient temperatures; and (D) shows the fitting curves of sensor loss spectrum and resonant wavelength under different ambient temperatures.

[0027] Figure 8 The effect of the thickness of the upper excitation layer on the sensor's loss spectrum and sensing performance is shown. Among them, (A) shows the relationship between the thickness of the upper excitation layer and the resonant wavelength under different applied magnetic fields; (B) shows the fitting curves of the sensor's loss spectrum and the resonant wavelength under different applied magnetic fields.

[0028] Figure 9 The effect of the lower excitation layer thickness on the sensor loss spectrum and sensing performance is shown. Among them, (A) shows the relationship between the lower excitation layer thickness and the resonant wavelength under different ambient temperatures; (B) shows the fitting curves of the sensor loss spectrum and the resonant wavelength under different ambient temperatures.

[0029] Figure 10 The graphs show the loss spectrum and resonant wavelength fitting curves of the sensor under different applied magnetic fields and ambient temperatures. Among them, (A) is the loss spectrum under different applied magnetic fields; (B) is the fitting curve of the resonant wavelength changing with the applied magnetic field; (C) is the loss spectrum under different ambient temperatures; and (D) is the fitting curve of the resonant wavelength changing with the ambient temperature. Detailed Implementation

[0030] The technical solution of the present invention will be described below with reference to embodiments. However, the present invention is not limited to the following embodiments. Unless otherwise specified, the experimental methods and detection methods described in each embodiment are conventional methods; unless otherwise specified, the reagents and materials can be purchased commercially.

[0031] Example 1 This embodiment provides a terahertz magnetic field and temperature sensor based on SPR-MOF.

[0032] like Figure 1As shown, the sensor in this embodiment uses a microstructured optical fiber (7) made of the cyclic olefin polymer Zeonex as the substrate material (radius 600 μm). The substrate material consists of a core and a cladding. Two layers of circular air holes are uniformly arranged in the cladding, and the air holes are arranged in a regular hexagonal lattice to form small air holes (1) in the cladding. The radius of each small air hole (1) in the cladding is 74 μm, and the center-to-center distance between adjacent small air holes (1) in the cladding is 250 μm. The core is located in the central region of the substrate material, that is, the Zeonex polymer region surrounded by the small air holes (1) in the cladding. A circular air hole, namely an enlarged air hole (2), is provided on each side of the core. The radius of the enlarged air hole (2) is 88 μm. The enlarged air hole (2) is used to reduce the average refractive index of the core in the vertical direction, so as to guide the light field energy to effectively leak to both sides of the core.

[0033] A planar polishing process is used on the upper and lower sides of the substrate material to form an upper polished surface and a lower polished surface at a distance of 300 μm from the center of the optical fiber. A molybdenum disulfide (MoS2) film with a thickness of 8.0 μm is prepared on the upper polished surface and the lower polished surface by chemical vapor deposition or transfer process. The MoS2 film serves as the surface plasmon resonance excitation layer, namely the upper excitation layer (3) and the lower excitation layer (4).

[0034] A magnetic field sensing material (5) is coated or encapsulated on the surface of the upper excitation layer (3) to obtain a magnetic field sensing channel; a temperature sensing material (6) is coated or encapsulated on the surface of the lower excitation layer (4) to obtain a temperature sensing channel (temperature sensing). The magnetic field sensing material (5) is selected as a water-based Fe3O4 magnetic fluid with a particle volume concentration of 1.8%; the temperature sensing material (6) is a conventional thermosetting polydimethylsiloxane (PDMS).

[0035] In this invention, the thickness of the magnetic field sensitive material and the temperature sensitive material is not particularly limited, as long as the thickness is sufficient to form a continuous covering layer on the surface of the upper and lower excitation layers, and the covering layer can cause a change in the effective refractive index of the interface.

[0036] The three-dimensional structure of the sensor described in this embodiment is as follows: Figure 2As shown in the figure. The sensor provided in this embodiment is connected to a broadband terahertz light source and a terahertz spectrometer at both ends, respectively. The output frequency range of the broadband terahertz light source is 0.2~0.5THz. The terahertz wave output from the terahertz light source is transmitted through the substrate material to the magnetic field and temperature sensing channel. The evanescent field of the fiber core mode penetrates to the surface of the MoS2 thin film under the guidance of amplified pores, exciting the surface plasmon polariton (SPP) mode. When the light wave meets the phase matching condition, the fiber core mode and the SPP mode resonantly couple, generating resonant absorption at a specific wavelength position, thereby forming two loss peaks on the transmission loss spectrum. By monitoring the wavelength shift of the two loss peaks in real time using the terahertz spectrometer, the changes in ambient magnetic field strength and temperature can be decoupled and inverted.

[0037] like Figure 3 As shown, under conditions of a magnetic field strength of 200 Oe and an ambient temperature of 20 ℃, the relationship between the resonant loss curve (black line for y-polarization, blue line for x-polarization) and the effective real part of the core mode refractive index (red line) of the sensor as a function of wavelength is illustrated. The results show that there is no resonance peak in the x-polarization direction, and the SPR effect is mainly excited by the y-polarization mode perpendicular to the excitation layer. At the phase-matching wavelength, a significant abrupt change occurs in the real part of the refractive index, and the optical field energy is coupled to the excitation layer on a large scale, thus forming a strong resonance loss peak in the y-polarization direction. The loss spectrum exhibits a bimodal characteristic: the left resonance peak originates from the SPP coupling of the magnetic field sensing channel, while the right resonance peak is excited by the temperature sensing channel. By tracking the wavelength shift of the bimodal peaks, synchronous and accurate detection of the magnetic field and temperature can be achieved.

[0038] Example 2 This embodiment demonstrates the impact of different cladding pore radii on sensor performance.

[0039] In this embodiment, the radii of the small air pores in the cladding are set to 66 μm, 68 μm, 70 μm, 72 μm and 74 μm respectively, while the other structural parameters remain unchanged.

[0040] Figure 4 (A) shows the relationship between the resonant wavelength and the magnetic field at an ambient temperature of 50℃, with the applied magnetic field increasing from 0 Oe to 200 Oe. The figure shows that as the radius of the small air hole increases, the energy confinement of the core mode strengthens, weakening the coupling between the core mode and the SPP mode, manifested as a decrease in the loss peak intensity and a blue shift in the resonant wavelength. Figure 4 As shown in (C), when the radius of the small air hole decreases, insufficient core confinement leads to a significant energy diffusion to the cladding, exciting higher-order SPP modes, which appear as shoulder peaks in the loss spectrum. From Figure 4As shown in (B) and (D), the magnetic field sensitivity decreases with increasing small air hole radius. However, it is worth noting that the quality factor and temperature sensitivity of both the magnetic field and temperature sensing channels reach their maximum values ​​when the small air hole radius is 74 μm. Based on a comprehensive consideration of the quality factor and magnetic field temperature sensitivity, and to avoid exciting higher-order SPP modes, 74 μm was ultimately selected as the optimal value for the small air hole radius.

[0041] Example 3 This embodiment illustrates the impact of different enlarged pore radii on sensor performance.

[0042] In this embodiment, the enlarged pore radius is set to 86 μm, 88 μm, 90 μm, 92 μm, and 94 μm, while other structural parameters remain unchanged. The effects of different enlarged pore radius values ​​on the loss spectrum and sensing performance are as follows: Figure 5 As shown. From Figure 5 As can be seen from (A) and (C), the change in the enlarged pore radius has little impact on the overall loss spectrum. Furthermore, the temperature sensitivity and the quality factors of the magnetic field and temperature sensing channel all reach their maximum values ​​when the enlarged pore radius is 88 μm. Figure 5 (B) and (D) in the figure indicate that the coupling efficiency between the core mode and the SPP mode is the highest at this point. Therefore, 88 μm is selected as the optimal value for amplifying the pores.

[0043] Example 4 This embodiment illustrates the impact of the spacing between small air holes in the cladding on sensor performance.

[0044] In this embodiment, the spacing between small air holes in adjacent cladding layers is set to 240 μm, 245 μm, 250 μm, 255 μm, and 260 μm, respectively, while the other structural parameters remain unchanged. Figure 6 The effect of different cladding air hole spacings on the loss spectrum and sensor performance is shown. For example... Figure 6 As shown in (A) and (C), increasing the spacing between the small air holes in the cladding reduces the refractive index difference between the core and the cladding and alters the phase-matching condition. This causes the resonance peaks of both the magnetic field and temperature sensing channels to first increase and then decrease, accompanied by a significant blue shift. In the temperature sensing channel ( Figure 6 In (C), the disruptive higher-order SPP modes excited by the small air hole spacing in the cladding disappear as the small air hole spacing in the cladding increases, significantly optimizing the mode coupling quality and spectral single-peak characteristics. Figure 6As shown in (B) and (D), the sensitivity of both the magnetic field and temperature sensing channels decreases monotonically with the increase of the spacing between the small air holes in the cladding. The quality factors of both the magnetic field and temperature sensing channels first increase and then decrease with the increase of the spacing between the small air holes in the cladding, reaching a relatively high value at 250 μm. Therefore, 250 μm is selected as the optimal spacing between the small air holes in the cladding.

[0045] Example 5 This embodiment illustrates the impact of polishing depth on sensor performance.

[0046] In this embodiment, the polishing depths are set to 290 μm, 295 μm, 300 μm, 305 μm, and 308 μm, respectively, while the other structural parameters remain unchanged. Figure 7 The effects of different polishing depths on the spectral characteristics and performance indicators of the magnetic field and temperature sensing channels are shown. Figure 7 As shown in (A) and (C), the coupling efficiency between the core mode and the SPP mode increases with increasing polishing depth, and the loss spectrum is significantly optimized. In the magnetic field sensing channel (magnetic field strength of 0 Oe), the optimal coupling point is at a polishing depth of 300 μm. In the temperature sensing channel (temperature of 20 ℃), the coupling efficiency is optimal at a polishing depth of 305 μm. Furthermore, from... Figure 7 As shown in (B) and (D), both the magnetic field sensitivity and temperature sensitivity decrease continuously with increasing polishing depth; however, when the polishing depth is 300 μm, the quality factors of both the magnetic field and temperature sensing channels are relatively good. Therefore, 300 μm is selected as the optimal polishing depth for the sensor.

[0047] Example 6 This embodiment illustrates the impact of the upper excitation layer thickness on sensor performance.

[0048] In this embodiment, the thickness of the upper excitation layer is set to 7.6 μm, 7.8 μm, 8.0 μm, 8.2 μm, and 8.4 μm, respectively, while the other structural parameters remain unchanged. Figure 8 The effects of different upper excitation layer thicknesses on the loss spectrum and sensor performance are shown. Figure 8 As shown in (A), under the condition of a magnetic field strength of 200 Oe, when the thickness of the upper excitation layer is 8.0 μm, the penetration depth of the core mode evanescent field into the SPP excitation layer is just enough to make the energy transfer efficiency the highest under the phase matching condition and the loss peak the most significant. Figure 8 Figure (B) shows that as the thickness of the upper excitation layer increases, the overall magnetic field sensitivity increases, while the quality factor first increases and then decreases, reaching its maximum value at 8.0 μm. Therefore, 8.0 μm is chosen as the optimal upper excitation layer thickness for the sensor.

[0049] Example 7 This embodiment illustrates the impact of the lower excitation layer thickness on sensor performance.

[0050] In this embodiment, the thickness of the lower excitation layer is set to 7.6 μm, 7.8 μm, 8.0 μm, 8.2 μm, and 8.4 μm, respectively, while the other structural parameters remain unchanged. Figure 9 The effects of different excitation layer thicknesses on the loss spectrum and sensor performance are presented. Figure 9 As shown in (A), under the condition of a magnetic field strength of 200 Oe, the energy coupling efficiency is the highest and the loss peak is the most significant when the thickness of the upper excitation layer is 8.0 μm. Figure 9 (B) indicates that as the thickness of the lower excitation layer increases, the temperature sensitivity increases, while the quality factor first increases and then decreases. Therefore, 8.0 μm is selected as the optimal lower excitation layer thickness for the sensor.

[0051] Example 8 This embodiment provides the sensing characteristics of the sensor under different applied magnetic fields and ambient temperatures.

[0052] Under an ambient temperature of 50 ℃, as the applied magnetic field gradually increases from 0 Oe to 500 Oe, the change in the sensor loss spectrum is as follows: Figure 10 As shown in (A), the fitting curve of the resonant wavelength as a function of the magnetic field is as follows: Figure 10 As shown in (B) of the figure, within the wavelength range of 82.1–111.4 μm, the resonant wavelength of peak 1 exhibits a nonlinear blue shift (R0) with increasing magnetic field strength. 2 =0.992), with a maximum magnetic field sensitivity of 0.226 μm / Oe. In contrast, the fitting curve of peak 2 is approximately a horizontal straight line, with the resonance wavelength always locked around 120.1 μm, proving that peak 2 is not sensitive to changes in the magnetic field.

[0053] Under an applied magnetic field of 0 Oe, as the ambient temperature gradually increases from 20 ℃ to 50 ℃, the change in the sensor loss spectrum is as follows: Figure 10 As shown in (C), the fitting curve of the resonant wavelength as a function of the magnetic field is as follows: Figure 10 As shown in (D), peak 1 shows a very weak response to ambient temperature, with its resonance wavelength shifting only from 111.4 μm to 111.7 μm. Peak 2, however, exhibits an approximately linear blue shift (R0) with increasing ambient temperature. 2 =0.975), with a maximum temperature sensitivity of 0.1 μm / ℃ and a maximum quality factor of 0.147 RIU. -1Furthermore, within the entire test range of the applied magnetic field and ambient temperature, the wavelength change windows of the applied magnetic field and ambient temperature are separate and do not overlap, indicating that the magnetic field sensing channel and temperature sensing channel of the sensor provided by this invention have excellent spectral independence and extremely low cross sensitivity, which can meet the needs of simultaneous detection of magnetic field and temperature parameters under complex environments.

[0054] The embodiments described above are some, but not all, of the embodiments of the present invention. The detailed description of the embodiments of the present invention is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art through related deductions and substitutions based on the inventive concept, without inventive effort, are within the scope of protection of the present invention.

Claims

1. A terahertz-band magnetic field and temperature sensor based on SPR-MOF, characterized in that, include: Microstructured optical fibers composed of the cyclic olefin polymer Zeonex are used as the substrate material; The substrate material consists of a fiber core and a cladding. The cladding has two layers of circular air holes arranged in a regular hexagonal lattice, serving as small air holes in the cladding. The fiber core is located in the central region of the substrate material, and a circular air hole is provided on each side of the fiber core, serving as enlarged air holes. The upper and lower sides of the substrate material are respectively provided with planar polished surfaces, serving as the upper polished surface and the lower polished surface; MoS2 thin films are respectively disposed on the upper polished surface and the lower polished surface, serving as the upper excitation layer and the lower excitation layer; The surface of the upper excitation layer is provided with a magnetic field sensitive material, and the surface of the lower excitation layer is provided with a temperature sensitive material.

2. The terahertz magnetic field and temperature sensor based on SPR-MOF according to claim 1, characterized in that, The magnetic field sensitive material is a water-based ferromagnetic fluid based on triferrooxide. The temperature-sensitive material is polydimethylsiloxane.

3. The terahertz magnetic field and temperature sensor based on SPR-MOF according to claim 2, characterized in that, The volume concentration of the water-based ferromagnetic fluid is 1.5% to 1.8%.

4. The terahertz magnetic field and temperature sensor based on SPR-MOF according to claim 1, characterized in that, The radius of the cladding air pores is 66~74 μm, and the spacing between adjacent cladding air pores is 240~260 μm.

5. The terahertz magnetic field and temperature sensor based on SPR-MOF according to claim 1, characterized in that, The radius of the enlarged pores is 86~94 μm.

6. The terahertz magnetic field and temperature sensor based on SPR-MOF according to claim 1, characterized in that, The polishing depth of the upper polishing surface and the lower polishing surface is 290~310 μm.

7. The terahertz magnetic field and temperature sensor based on SPR-MOF according to claim 1, characterized in that, The thickness of the MoS2 film is 7.6~8.4 μm.

8. The terahertz magnetic field and temperature sensor based on SPR-MOF according to claim 1, characterized in that, The sensor has a magnetic field detection range of 0~500 Oe and a temperature detection range of 20~50℃.

9. The terahertz magnetic field and temperature sensor based on SPR-MOF according to claim 1, characterized in that, The sensor has a magnetic field detection sensitivity of 0.226 μm / Oe and a temperature detection sensitivity of 0.1 μm / ℃.

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