A fully-quartz-encapsulated doped quartz whispering gallery microsphere sensor and a preparation method thereof

Abstract

The application relates to a full-quartz-encapsulated doped quartz whispering gallery microsphere sensor and a preparation method thereof, and belongs to the technical field of microcavity lasers. The full-quartz-encapsulated doped quartz whispering gallery microsphere sensor comprises a quartz substrate, a T-shaped groove is engraved on the quartz substrate, a fiber taper is transversely placed in the T-shaped groove of the quartz substrate, a doped quartz whispering gallery microsphere is vertically placed in the T-shaped groove of the quartz substrate, and the doped quartz whispering gallery microsphere is directly in contact with the fiber taper for coupling. The full-quartz-encapsulated doped quartz whispering gallery microsphere sensor provided by the application encapsulates the fiber taper-microsphere coupling system in the groove of the quartz substrate, has the characteristics of miniaturization, high integration and stable structure, and has good reliability in high-temperature, high-pressure and corrosive environments, and is suitable for various high-temperature measurement and detection scenes.

Description

Technical Field

[0001] This application relates to the field of microcavity laser technology, and in particular to a fully quartz-encapsulated doped quartz whispering-gallery microsphere sensor and its fabrication method. Background Technology

[0002] Optical whispering-gallery mode microcavities confine light within a cavity, allowing it to propagate via total internal reflection. They offer advantages such as a high quality factor and small mode volume, and are widely used in high-sensitivity sensing, low-threshold lasers, optical filtering, and nonlinear optics. In low-threshold microcavity lasers, whispering-gallery mode-based microcavity laser devices utilize low-absorption and low-scattering gain medium materials to confine light within the equatorial plane of a ring-shaped microcavity for extended periods through continuous total internal reflection, effectively exciting doped rare-earth ions. Simultaneously, changes in environmental parameters (such as refractive index, temperature, or strain) modulate the lasing wavelength of the microcavity laser, causing a redshift or blueshift. This characteristic makes it suitable as a high-sensitivity environmental sensor.

[0003] In various whispering-gallery microcavities, microspheres possess advantages such as low optical loss, simple structure, and ease of fabrication, making them an ideal platform for realizing low-threshold, narrow-linewidth lasers. However, existing methods for fabricating doped quartz whispering-gallery microspheres are complex, time-consuming, and have low material utilization. Furthermore, traditional doped quartz whispering-gallery microsphere sensors based on UV adhesive encapsulation exhibit poor stability, are susceptible to high temperatures and corrosion, thus limiting their industrial application. Summary of the Invention

[0004] In view of this, this application provides a fully quartz-encapsulated doped quartz whispering-gallery microsphere sensor and its preparation method, so as to achieve rapid preparation and stable packaging of the doped quartz whispering-gallery microsphere sensor, which can effectively overcome the defects of the prior art.

[0005] The first aspect of this application provides a fully quartz-encapsulated doped quartz whispering-gallery microsphere sensor, the fully quartz-encapsulated doped quartz whispering-gallery microsphere sensor comprising:

[0006] A quartz substrate, on which a T-shaped groove is engraved;

[0007] An optical fiber taper, wherein the optical fiber taper is placed laterally inside a T-shaped groove in the quartz substrate;

[0008] The doped quartz whispering wall microspheres, with their pigtails attached, are vertically placed inside a T-shaped groove in the quartz substrate, and are directly coupled to the fiber taper.

[0009] Preferably, the tapered fiber and the doped quartz whispering gallery mode microsphere are contact coupled, and the tail fiber of the doped quartz whispering gallery mode microsphere and the two ends of the tapered fiber are fixed in the T-shaped groove by fused quartz.

[0010] Preferably, the depth of the T-shaped groove is 200-2000 μm.

[0011] Preferably, the taper region diameter of the tapered fiber is 1.5±0.5 μm, the cladding outer diameter of the two ends of the tapered fiber is 125±0.9 μm, and the core of the tapered fiber is 10.4±0.8 μm.

[0012] Preferably, the rare earth ions doped in the doped quartz whispering gallery mode microsphere are selected from at least one of Er 3+ , Yr 3+ , Ce 3+ , Nd 3+ , Ho 3+ , Tm 3+ .

[0013] The laser wavelength excited by the doped quartz whispering gallery mode microsphere can be red-shifted or blue-shifted with the change of the external refractive index, temperature or strain. Specifically, when the external refractive index of the microsphere changes, the effective refractive index of the whispering gallery mode microsphere also changes, thereby changing the resonant wavelength. When the external temperature of the microsphere changes, the size and refractive index of the microsphere change due to the thermal light effect and thermal expansion effect of the microsphere cavity, thereby changing the resonant wavelength and further changing the laser wavelength. Therefore, by tracking the laser wavelength excited by the doped quartz whispering gallery mode microsphere, the monitoring of the environmental parameters can be realized.

[0014] The second aspect of the present application further provides a preparation method of the above-mentioned all-quartz packaged doped quartz whispering gallery mode microsphere sensor, comprising the following steps:

[0015] S1, preparing a quartz slurry and a doped rare earth ion quartz slurry: mixing SiO2 powder, Al2O3 and deionized water in a certain mass ratio to obtain a quartz slurry; mixing a compound containing rare earth ions, SiO2 powder, Al2O3 and deionized water in a certain mass ratio, putting them into a planetary ball mill for grinding for two days, and then adding HPMC to obtain a ground mixed material; putting the ground mixed material into a vacuum defoaming stirrer for stirring and defoaming to obtain a doped rare earth ion quartz slurry with moderate viscosity, no bubbles and no clumps;

[0016] S2, preparing the doped quartz echo-wall microsphere: the doped rare earth ion-containing quartz slurry is loaded into a precision dispensing machine; one end of a single-mode optical fiber with a PVC sleeve is stripped of the sleeve and coating layer to obtain a single-mode optical fiber with no coating layer, and the single-mode optical fiber is cut flat with an optical fiber cutting knife, and then clamped into an electric optical fiber rotating clamp, and the electric optical fiber rotating clamp clamping the single-mode optical fiber is fixed on a high-precision three-dimensional displacement table; under the observation of a CCD, the doped rare earth ion-containing quartz slurry is extruded and coated onto the cladding surface of the optical fiber clamped by the electric optical fiber rotating clamp by controlling the movement of the three-dimensional displacement table and the extrusion speed and time of the precision dispensing machine; the movement of the high-precision three-dimensional displacement table is controlled to make the CO2 laser beam vertically irradiate the single-mode optical fiber on which the doped rare earth ion-containing quartz slurry is coated on the cladding surface; the switch of the electric optical fiber rotating clamp is turned on to make the optical fiber rotate at a certain speed; meanwhile, the light output power, light output time and focusing height of the CO2 laser are set; the laser is turned on, and the single-mode optical fiber coated with the doped rare earth ion-containing quartz slurry is melted under the action of laser heating, and at the same time, the doped quartz echo-wall microsphere with uniform quality distribution is formed in the rotating process.

[0017] S3, preparing a doped quartz echo-wall microsphere sensor packaged with quartz: a T-shaped groove is etched on a quartz substrate using a CO2 laser; an optical fiber taper drawn by a hydrogen-oxygen flame method is laterally placed in the T-shaped groove, and quartz slurry is coated on both ends of the optical fiber taper; the coated quartz slurry is dried and sintered by heating with a CO2 laser to form fused quartz to fix the optical fiber taper; under the observation of a CCD, the doped quartz echo-wall microsphere is coupled with the optical fiber taper by using a three-dimensional displacement table, and the doped quartz echo-wall microsphere is vertically placed in the T-shaped groove; the tail fiber of the doped quartz echo-wall microsphere is coated with quartz slurry, and after drying and sintering, fused quartz is formed to realize the full quartz packaging of the doped quartz echo-wall microsphere.

[0018] Preferably, in step S1, the rare earth ion-containing compound is ErCl3 and YrCl3.

[0019] Preferably, in step S1, the stirring and degassing time of the vacuum degassing stirrer is 5-10 min, and the stirring speed is 1000-2000 r / min.

[0020] Preferably, in step S2, the extrusion speed of the precision dispensing machine is 5-20 μL / min, and the extrusion time is 1 s; the rotating speed of the electric optical fiber rotating clamp is 300-1000 r / min; the light output power of the CO2 laser is 25 W, the light output time is 0.5 s, and the focusing height is 6 cm.

[0021] Preferably, in step S3, the power of the CO2 laser for drying the quartz slurry is 5 W, and the power for sintering the quartz slurry is 25 W.

[0022] Compared with the prior art, the application has the following beneficial effects:

[0023] 1、The full-quartz packaged doped quartz whispering gallery microsphere sensor provided by the application encapsulates the fiber taper-microsphere coupling system in the quartz substrate groove, has the characteristics of miniaturization, high integration, stable structure and the like, and exhibits good reliability in high-temperature, high-pressure, corrosion and the like environments, and is suitable for various high-temperature measurement and detection scenes.

[0024] 2、The preparation method of the doped quartz whispering gallery microsphere provided by the application is short in time consumption, high in material utilization rate, and flexible in material selection, and different doped rare earth ion whispering gallery microspheres can be prepared according to needs to realize the preparation of microsphere lasers with different laser wavebands. BRIEF DESCRIPTION OF DRAWINGS

[0025] In order to more clearly illustrate the technical solutions in the application or the prior art, the drawings needed to be used in the description of the application or the prior art will be briefly introduced below. Obviously, the drawings in the following description are some embodiments of the application, and other drawings can also be obtained by those skilled in the art without creative labor on the basis of these drawings.

[0026] Figure 1 It is a structure schematic diagram of the full-quartz packaged doped quartz whispering gallery microsphere sensor in the application;

[0027] Figure 2 It is a preparation flow of the full-quartz packaged doped quartz whispering gallery microsphere sensor in the application;

[0028] Figure 3 It is an SEM diagram of the doped quartz whispering gallery microsphere prepared in the application;

[0029] Figure 4 It is an end face micrograph of the fiber taper packaging place encapsulated in the quartz substrate groove in the application;

[0030] Figure 5 It is a surface profile diagram of the doped quartz whispering gallery microsphere prepared in the application;

[0031] Figure 6 It is a transmission spectrum of the doped quartz whispering gallery microsphere before and after full-quartz packaging in the application;

[0032] Figure 7 It is a laser characteristic of the Er 3+ / Yr 3+ co-doped microsphere prepared in the application, wherein (a) is a multimode laser characteristic curve, and (b) is a laser threshold curve;

[0033] Figure 8 It is a laser characteristic of the Er 3+ / Yr3+ The spectral curves of laser wavelength change with temperature for co-doped microspheres, where (a) is the wavelength drift of laser wavelength with temperature change, and (b) is the linear relationship between laser wavelength drift and temperature change.

[0034] Explanation of reference numerals in the attached figures:

[0035] 1. Doped quartz whispering-gallery microspheres; 2. Fiber optic taper; 3. Quartz substrate; 4. Precision dispensing machine; 5. Single-mode fiber optic cable with coating removal; 6. Motorized fiber optic rotating clamp; 7. CO2 laser beam; 8. Quartz slurry. Detailed Implementation

[0036] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0037] Unless otherwise specified, the experimental methods used in the embodiments of this application are all conventional methods.

[0038] In the following examples, unless otherwise specified, all raw materials can be obtained by commercial purchase or conventional methods.

[0039] Example 1:

[0040] This embodiment provides a fully quartz-encapsulated doped quartz whispering-gallery microsphere sensor, such as... Figure 1 As shown, the structure includes a doped quartz whispering wall microsphere 1, an optical fiber taper 2, and a quartz substrate 3 with T-shaped grooves. In the fully quartz-encapsulated doped quartz whispering wall microsphere sensor structure, the doped quartz whispering wall microsphere 1 is directly coupled to the optical fiber taper 2. The doped quartz whispering wall microsphere 1 is placed vertically inside the quartz substrate 3 with T-shaped grooves, and the optical fiber taper 2 is placed horizontally inside the quartz substrate 3 with T-shaped grooves. The pigtail of the doped quartz whispering wall microsphere 1 and the two ends of the optical fiber taper 2 are fixed by fused quartz formed from dried and sintered quartz slurry.

[0041] Specifically, the doped quartz whispering wall microsphere 1 and the fiber taper 2 are first contacted and coupled, and then the pigtail of the doped quartz whispering wall microsphere 1 and the two ends of the fiber taper 2 are fixed by fused silica, so as to achieve stable encapsulation of the coupling system of the doped quartz whispering wall microsphere 1 and the fiber taper 2 in the T-shaped groove.

[0042] For example, in the doped quartz whispering-gallery microspheres 1, the spherical ones are microspheres, and the columnar ones are microsphere tails. Figure 1The middle part of the fiber taper 2 is coupled with the circular microsphere in the doped quartz whispering gallery microsphere 1, and the tail fiber is fixed by fused quartz.

[0043] The two ends of the fiber taper 2 are connected to a 980 nm laser and a spectrometer respectively. The doped quartz whispering gallery microsphere 1 can realize laser emission under 980 nm pumping. When the external environmental parameters such as refractive index, temperature, pressure and the like change, the laser wavelength will be red-shifted or blue-shifted, and then the change of the laser wavelength of the doped quartz whispering gallery microsphere 1 can be used to measure the environmental parameters.

[0044] In the embodiment, the diameter of the doped quartz whispering gallery microsphere 1 is 300±50 μm, the taper region diameter of the fiber taper 2 is 1.5±0.5 μm, the cladding outer diameter of the fiber taper 2 at both ends is 125±0.9 μm, and the core is 10.4±0.8 μm. The quartz substrate 3 engraved with a T-shaped groove has a thickness of 3 mm, and the T-shaped groove is etched by a CO2 laser, with a depth of 200 μm.

[0045] Embodiment 2:

[0046] The embodiment provides a full-quartz packaged doped quartz whispering gallery microsphere sensor manufacturing method, and the flow is as shown in Figure 2 , and specifically includes the following steps:

[0047] Step 1: Mix SiO2 powder, Al2O3 and deionized water according to a certain mass ratio to obtain a quartz slurry; weigh and mix a compound containing rare earth ions, SiO2 powder, Al2O3 and deionized water according to a certain mass ratio (specifically, the mass ratio of SiO2 powder, deionized water, ErCl3, YrCl3 and Al2O3 is 47.5:47.5:0.75:0.75:3.5), put into a planetary ball mill for grinding for two days, then add HPMC to obtain the ground mixed material; put the ground mixed material into a vacuum defoaming stirrer for stirring and defoaming, in the embodiment, the stirring and defoaming time of the vacuum defoaming stirrer is 5-10 min, and the stirring speed is 1000-2000 r / min, to obtain a doped rare earth ion quartz slurry with moderate viscosity, no bubbles and no agglomeration;

[0048] In the embodiment, the doped rare earth ions are Er 3+ and Yr 3+ ions, which can also be Er 3+ , Yr 3+ , Ce 3+ , Nd 3+ , Ho 3+ , Tm 3 and the like fluorescent ions. +

[0049] Step 2: as Figure 2As shown in Figure ①, rare-earth ion-doped quartz slurry is loaded into a precision dispensing machine 4; the PVC sheath and coating are stripped from one end of a single-mode optical fiber to obtain a coated single-mode optical fiber 5, which is then cut flat with a fiber optic cleaver and clamped into an electric optical fiber rotating fixture 6. The electric optical fiber rotating fixture 6 holding the single-mode optical fiber is fixed on a high-precision three-dimensional displacement stage; under the observation of a CCD, the movement of the three-dimensional displacement stage and the extrusion speed and time of the precision dispensing machine 4 are controlled. In this embodiment, the extrusion speed of the precision dispensing machine 4 is 5~20 μL / min, and the extrusion time is fixed at 1 s. The rare-earth ion-doped quartz slurry is extruded and coated onto the cladding surface of the optical fiber held by the electric optical fiber rotating fixture 6; as shown in Figure ①. Figure 2 As shown in Figure ②, the movement of the high-precision three-dimensional displacement stage is controlled to make the CO2 laser beam 7 perpendicularly irradiate the single-mode optical fiber whose cladding surface is coated with rare-earth ion-doped quartz paste; the switch of the electric optical fiber rotating clamp 6 is turned on, and the rotation speed of the electric optical fiber rotating clamp 6 is controlled to be 300~1000 r / min, so that the optical fiber rotates at a certain speed. In this embodiment, the rotation speed of the electric optical fiber rotating clamp 6 is 1000 r / min; Figure 2 As shown in Figure ②, the output power, output time, and focusing height of the CO2 laser are set simultaneously. In this embodiment, the output power of the CO2 laser is 25 W, the output time is 0.5 s, and the focusing height is 6 cm. When the laser is turned on, the single-mode optical fiber coated with rare earth ion-doped quartz paste melts under the action of laser heating. At the same time, during the rotation process, doped quartz whispering wall microspheres 1 with uniform mass distribution are formed. The diameter of the doped quartz whispering wall microspheres 1 is 300±50 μm.

[0050] Step 3: As Figure 2 As shown in Figure ③, a T-shaped groove is etched into the quartz substrate 3 using a CO2 laser. In this embodiment, the depth of the T-shaped groove etched into the quartz substrate 3 is 200 μm. An oxyhydrogen flame-drawn fiber taper 2 is then placed laterally inside the T-shaped groove. In this embodiment, the diameter of the taper region of the oxyhydrogen flame-drawn fiber taper 2 is 2 μm, and quartz paste 8 is coated at both ends of the fiber taper. Quartz paste is then coated at both ends of the fiber taper 2 using a precision dispensing machine 4. The fiber taper 2 is fixed after the quartz paste 8 is dried and sintered using a CO2 laser. The power of the CO2 laser for heating and drying the quartz paste 8 is 5 W, and the power of the CO2 laser for sintering the quartz paste 8 is 25 W. Figure 2 As shown in Figure ④, under the observation of a CCD, the prepared doped quartz whispering microsphere 1 is coupled with an optical fiber taper 2. The tail fiber of the doped quartz whispering microsphere 1 is placed vertically in the T-shaped groove of the quartz substrate 3. The quartz paste 8 coated on the tail fiber is dried and sintered to realize the full quartz encapsulation of the doped quartz whispering microsphere sensor.

[0051] Figure 3SEM image of the doped quartz acoustic resonator microsphere prepared in the embodiment, the doped rare earth ion is Er 3+ / Yr 3+ Ion, the microsphere diameter is 280 μm.

[0052] Figure 4 Micrograph of the end face of the fiber taper packaging site packaged in the groove of the quartz substrate in the embodiment, the CO2 laser heats the sintered quartz slurry to form a molten quartz, which is fused with the surface of the single-mode fiber cladding to realize the fixation of the fiber taper.

[0053] Figure 5 Surface profile graph of the doped quartz acoustic resonator microsphere prepared in the embodiment, the surface Sa (surface arithmetic average height) of the microsphere measured by the profiler is 1.112 nm.

[0054] Figure 6 Transmittance spectrum of the doped quartz acoustic resonator microsphere before and after the all-quartz packaging in the embodiment, the Q value of the microsphere measured before the quartz packaging is 4×10 5 , and the Q value of the microsphere measured after the quartz packaging is 3.1×10 5 .

[0055] Figure 7 Laser property curve of the Er 3+ / Yr 3+ co-doped microsphere prepared in the embodiment, wherein Figure 7 (a) in the figure is the multimode laser property of the prepared Er 3+ / Yr 3+ co-doped microsphere under the pumping of the 980 nm laser, which realizes the laser emission near the 1080 nm and 1590 nm wave bands, Figure 7 (b) in the figure is the laser threshold curve of the Er 3+ / Yr 3+ co-doped microsphere under the pumping of the 980 nm laser, and the laser threshold is 182 μW.

[0056] Figure 8 Spectrum curve of the laser wavelength of the Er 3+ / Yr 3+ co-doped microsphere prepared in the embodiment with the change of temperature, wherein Figure 8 (a) in the figure is the wavelength drift of the laser wavelength at the temperature of 300-380 ℃, Figure 8 (b) in the figure is the linear response of the laser wavelength of the prepared Er 3+ / Yr 3+ co-doped microsphere at the temperature of 300-380 ℃, and the temperature sensitivity is 11.80 pm / ℃.

[0057] The full-quartz packaged doped quartz whispering gallery microsphere sensor provided in the application encapsulates the fiber taper-microsphere coupling system in a groove of a quartz substrate, has the characteristics of miniaturization, high integration, stable structure and the like, and exhibits good reliability in high-temperature, high-pressure, corrosion and the like environments, and is suitable for various high-temperature measurement and detection scenes.

[0058] The preparation method of the doped quartz whispering gallery microsphere provided in the application is short in time consumption, high in material utilization rate, and flexible in material selection, and different doped rare earth ion whispering gallery microspheres can be prepared according to needs to realize preparation of microsphere lasers with different laser wave bands.

[0059] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the application, and not to limit them; although the application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that: it can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacement for part or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the application.

Claims

1. A fully quartz-encased doped quartz whispering gallery microsphere sensor, characterized in that, The full-quartz-encapsulated doped quartz whispering gallery microsphere sensor comprises: a quartz substrate with a T-shaped groove engraved thereon; a fiber taper laterally placed inside the T-shaped groove of the quartz substrate; a doped quartz whispering gallery microsphere with a tail fiber vertically placed inside the T-shaped groove of the quartz substrate and directly contacted and coupled with the fiber taper; The preparation method of the full-quartz-encapsulated doped quartz whispering gallery microsphere sensor comprises the following steps: S1, preparing a quartz slurry and a doped rare earth ion quartz slurry: mixing SiO2 powder, Al2O3 and deionized water in a certain mass ratio to obtain a quartz slurry; mixing a compound containing rare earth ions, SiO2 powder, Al2O3 and deionized water in a certain mass ratio, putting them into a planetary ball mill for grinding for two days, then adding HPMC to obtain a ground mixed material; putting the ground mixed material into a vacuum defoaming stirrer to stir and defoam, thereby preparing a doped rare earth ion quartz slurry with moderate viscosity, no bubbles and no clumps; S2, preparing a doped quartz whispering gallery microsphere: loading the doped rare earth ion quartz slurry into a precision dispensing machine; peeling off the sleeve and coating layer from one end of a section of single-mode optical fiber with a PVC sleeve to obtain a single-mode optical fiber with the coating layer removed, and cutting it flat with an optical fiber cutting knife, then clamping it into an electric optical fiber rotating clamp, and fixing the electric optical fiber rotating clamp clamping the single-mode optical fiber on a high-precision three-dimensional displacement table; under the observation of a CCD, the doped rare earth ion quartz slurry is extruded and coated onto the surface of the optical fiber cladding clamped by the electric optical fiber rotating clamp by controlling the movement of the three-dimensional displacement table and the extrusion speed and time of the precision dispensing machine; controlling the movement of the high-precision three-dimensional displacement table to make the CO2 laser beam vertically irradiate the single-mode optical fiber with the doped rare earth ion quartz slurry coated on the cladding surface; turning on the electric optical fiber rotating clamp switch to make the optical fiber rotate at a certain speed; at the same time, setting the CO2 laser output power, light output time and focusing height; turning on the laser, and the single-mode optical fiber coated with the doped rare earth ion quartz slurry melts under the action of laser heating, and forms a doped quartz whispering gallery microsphere with uniform mass distribution in the rotating process; S3, preparing a full-quartz-encapsulated doped quartz whispering gallery microsphere sensor: using a CO2 laser to etch a T-shaped groove on a quartz substrate; laterally placing a fiber taper drawn by a hydrogen-oxygen flame method into the T-shaped groove, and coating quartz slurry on both ends of the fiber taper; using a CO2 laser to heat, dry and sinter the coated quartz slurry to form fused quartz to fix the fiber taper; under the observation of a CCD, the doped quartz whispering gallery microsphere is coupled with the fiber taper by using a three-dimensional displacement table, and the doped quartz whispering gallery microsphere is vertically placed inside the T-shaped groove; coating the tail fiber of the doped quartz whispering gallery microsphere with quartz slurry, and forming fused quartz after drying and sintering to realize full-quartz encapsulation of the doped quartz whispering gallery microsphere.

2. The all-quartz encapsulated doped quartz whispering gallery mode microsphere sensor of claim 1, wherein, The fiber taper and the doped quartz whispering gallery microsphere are contact coupled, and the tail fiber of the doped quartz whispering gallery microsphere and both ends of the fiber taper are fixed in the T-shaped groove by fused quartz.

3. The all-quartz encapsulated doped quartz whispering gallery mode microsphere sensor of claim 1, wherein, The depth of the T-shaped groove is 200-2000 microns.

4. The all-quartz encapsulated doped quartz whispering gallery mode microsphere sensor of claim 2, wherein, The taper region diameter of the fiber taper is 1.5+ / -0.5 microns, the outer diameter of the cladding at both ends of the fiber taper is 125+ / -0.9 microns, and the core of the fiber taper is 10.4+ / -0.8 microns.

5. The all-quartz encapsulated doped quartz whispering gallery mode microsphere sensor of claim 1, wherein, The rare earth ions doped inside the doped quartz whispering gallery microsphere are selected from at least one of Er 3+ , Yr 3+ , Ce 3+ , Nd 3+ , Ho 3+ , Tm 3+ .

6. The all-quartz encapsulated doped quartz whispering gallery mode microsphere sensor of claim 1, wherein, In step S1, the compound containing rare earth ions is ErCl3 and YrCl3.

7. The all-quartz encapsulated doped quartz whispering gallery mode microsphere sensor of claim 1, wherein, In step S1, the stirring and defoaming time of the vacuum defoaming stirrer is 5-10 min, and the stirring speed is 1000-2000 r / min.

8. The all-quartz encapsulated doped quartz whispering gallery mode microsphere sensor of claim 1, wherein, In step S2, the extrusion speed of the precision glue dispenser is 5-20 microliters / min, the extrusion time is 1 second; the rotation speed of the electric fiber rotating clamp is 300-1000 r / min; the light output power of the CO2 laser is 25 W, the light output time is 0.5 seconds, and the focusing height is 6 cm.

9. The all-quartz encapsulated doped quartz whispering gallery mode microsphere sensor of claim 1, wherein, In step S3, the power of the CO2 laser for heating and drying the quartz slurry is 5 W, and the power for sintering the quartz slurry is 25 W.

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