A quantum all-optical temperature sensing method and system based on silicon carbide color center

Abstract

This invention provides a quantum all-optical temperature sensing method and system based on silicon carbide color centers. The method includes: emitting a laser of a preset wavelength to an optical temperature sensor, wherein the optical temperature sensor is composed of silicon carbide color centers; acquiring Stokes fluorescence and anti-Stokes fluorescence reflected by the optical temperature sensor; calculating the intensity ratio of the Stokes fluorescence and the anti-Stokes fluorescence based on the photon counts corresponding to each of the Stokes fluorescence and the anti-Stokes fluorescence; and calculating the real-time temperature of the optical temperature sensor based on the intensity ratio and a preset intensity ratio-temperature function, wherein the intensity ratio-temperature function is obtained by fitting experimental data after conducting several optical temperature sensing experiments on the silicon carbide color centers, thereby improving the sensitivity and stability of optical thermal measurement.

Description

Technical Field

[0001] This invention relates to the field of optical thermal measurement technology, and in particular to a quantum all-optical temperature sensing method and system based on silicon carbide color centers. Background Technology

[0002] Recently, the field of nanoscale optical thermal measurement has seen significant growth, becoming increasingly important across disciplines such as materials science, biophotonics, and especially semiconductor engineering. Among numerous thermal sensor platforms, such as fluorescent dyes and nanoparticles, diamond quantum defects have attracted considerable attention and shown particular potential due to their durability, biocompatibility, and wide operating temperature range, even under challenging environmental conditions. Traditional thermal measurement methods typically rely on the photonic properties of optically detected magnetic resonance (ODMR) or zero phonon lines (ZPL). However, ODMR methods are hampered by microwave-induced heating and sensitivity to magnetic field noise, while the ZPL protocol requires continuous spectral analysis, limiting their speed and temperature resolution.

[0003] Researchers have discovered that temperature can be sensed by measuring the intensity ratio between the anti-Stokes and Stokes emissions of a color center, and this method boasts high real-time performance, high-temperature sensitivity, and high spatial resolution at the diffraction limit. With the continuous miniaturization of electronic components, efficient thermal management is crucial to avoiding heat buildup and potential compromise to device integrity. Integrating this thermal measurement technology into semiconductor processes, particularly with CMOS compatibility, opens new possibilities for the computer and electronics fields, positioning nanoscale optical thermal measurement as a cornerstone for future technological and medical breakthroughs. Summary of the Invention

[0004] To address the aforementioned technical problems, this invention provides a quantum all-optical temperature sensing method and system based on silicon carbide color centers, which utilizes silicon carbide color centers to achieve all-optical temperature measurement and improves the sensitivity and stability of optical thermal measurement.

[0005] In a first aspect, the present invention provides a quantum all-optical temperature sensing method based on silicon carbide color centers, comprising:

[0006] A laser of a preset wavelength is emitted toward an optical temperature sensor, wherein the optical temperature sensor is composed of silicon carbide color centers;

[0007] Acquire the Stokes fluorescence and anti-Stokes fluorescence reflected by the optical temperature sensor;

[0008] The intensity ratio of the Stokes fluorescence and the anti-Stokes fluorescence is calculated based on the photon counts corresponding to the Stokes fluorescence and the anti-Stokes fluorescence, respectively.

[0009] The real-time temperature of the optical temperature sensor is calculated based on the intensity ratio and a preset intensity ratio-temperature function. The intensity ratio-temperature function is obtained by fitting experimental data after conducting several optical temperature sensing experiments on the silicon carbide color center.

[0010] This invention provides a quantum all-optical temperature sensing method based on silicon carbide color centers. When a color center is excited by a specific external laser, electrons transition to higher energy levels. When an electron transitions to a lower energy level, it releases energy in the form of photons; this is photoluminescence of the color center. This invention utilizes this characteristic of color centers to construct an optical temperature sensor composed of silicon carbide color centers. Stokes fluorescence and anti-Stokes fluorescence of the optical temperature sensor are excited by a preset laser. Since the intensity of both Stokes fluorescence and anti-Stokes fluorescence follows an Arrhenius exponential relationship with temperature, by collecting these two types of fluorescence and calculating the fluorescence intensity ratio using the photon counts corresponding to each fluorescence, the real-time temperature of the optical temperature sensor can be calculated based on the fluorescence intensity ratio. This achieves all-optical temperature measurement based on silicon carbide color centers. This invention utilizes dual fluorescence intensity to calculate temperature, which has higher accuracy compared to single fluorescence methods. Subsequent experiments demonstrate that, compared to existing technologies, the temperature sensing method provided by this invention has higher sensitivity and stability.

[0011] Furthermore, the emission of a laser of a preset wavelength to the optical temperature sensor includes:

[0012] The laser is coupled using a single-mode fiber and the laser is passed through a lens to form parallel light.

[0013] The parallel light is focused onto the optical temperature sensor using an air objective lens with a preset numerical aperture.

[0014] This embodiment of the invention further describes the specific process of laser emission. First, a laser is coupled through a single-mode fiber, and then converted into parallel light through a lens. Finally, the parallel light is focused onto the optical temperature sensor through an air objective lens with a preset numerical aperture, thus achieving the excitation of silicon carbide color centers using laser light. In specific application scenarios, the optical temperature sensor can be pre-attached to the surface of the object to be measured, and a corresponding laser emission device can be constructed based on the laser emission method provided in this embodiment. When it is necessary to measure the temperature of the object, the laser emission device emits a laser towards the optical temperature sensor, achieving non-contact temperature measurement and improving the convenience of temperature measurement.

[0015] In one possible implementation, acquiring the Stokes fluorescence and anti-Stokes fluorescence reflected by the optical temperature sensor includes:

[0016] The fluorescence reflected by the optical temperature sensor is obtained through the objective lens;

[0017] The fluorescence was split into Stokes fluorescence and anti-Stokes fluorescence using a beam splitter and emitted in different directions.

[0018] The Stokes fluorescence is obtained using a first filter, and the anti-Stokes fluorescence is obtained using a second filter, wherein the transmittance wavelengths of the first filter and the second filter are different.

[0019] This invention provides a method for obtaining Stokes fluorescence and anti-Stokes fluorescence. After the optical temperature sensor is excited by a laser, the optical temperature sensor will radiate fluorescence along a path opposite to that of the laser. Therefore, the fluorescence reflected by the optical temperature sensor can be accurately obtained through an objective lens along the path of laser emission. Then, a beam splitter is used to split the fluorescence into Stokes fluorescence and anti-Stokes fluorescence, which are emitted in different directions. The Stokes fluorescence and anti-Stokes fluorescence are then obtained through different filters in the different directions, thus preparing data for subsequent temperature calculations.

[0020] In one possible implementation, calculating the intensity ratio of the Stokes fluorescence and the anti-Stokes fluorescence based on the photon counts corresponding to the respective Stokes fluorescence and anti-Stokes fluorescence includes:

[0021] Based on the detector's sensitivity to the spectrum, different detectors are used to perform spectral measurements on the Stokes fluorescence and anti-Stokes fluorescence respectively, and the corresponding photon counts are obtained.

[0022] The intensity ratio of the Stokes fluorescence and the anti-Stokes fluorescence is calculated based on the corresponding photon counts.

[0023] In this embodiment of the invention, after acquiring the Stokes fluorescence and anti-Stokes fluorescence, the spectra of the Stokes fluorescence and anti-Stokes fluorescence are measured using different detectors to obtain the corresponding photon counts, and then the intensity ratio of the Stokes fluorescence and the anti-Stokes fluorescence is calculated. By calculating the intensity ratio of the two fluorescences, the intensity data of Stokes fluorescence and anti-Stokes fluorescence can be effectively utilized. Furthermore, since the intensity of both fluorescences follows an Arrhenius exponential relationship with temperature, the intensity ratio data can more accurately fit the temperature change curve of the optical temperature sensor compared to the intensity data of a single fluorescence, resulting in a higher sensitivity and stability for the subsequently constructed intensity ratio-temperature function.

[0024] Furthermore, the real-time temperature of the optical temperature sensor is calculated based on the intensity ratio and a preset intensity ratio-temperature function, using the following formula:

[0025]

[0026] Where y is the intensity ratio, T is the real-time temperature of the optical temperature sensor, T0 is the initial temperature of the optical temperature sensor, a, b, and c are parameters obtained by fitting experimental data after conducting several optical temperature sensing experiments on the silicon carbide color center, and e is the natural base.

[0027] Secondly, the present invention provides a quantum all-optical temperature sensing system based on silicon carbide color centers, including a laser emission module, an acquisition module, an intensity ratio calculation module, and a temperature calculation module;

[0028] The laser emitting module is used to emit laser light of a preset wavelength to the optical temperature sensor, wherein the optical temperature sensor is composed of silicon carbide color centers.

[0029] The acquisition module is used to acquire the Stokes fluorescence and anti-Stokes fluorescence reflected by the optical temperature sensor;

[0030] The intensity ratio calculation module is used to calculate the intensity ratio of the Stokes fluorescence and the anti-Stokes fluorescence based on the photon counts corresponding to the Stokes fluorescence and the anti-Stokes fluorescence, respectively.

[0031] The temperature calculation module is used to calculate the real-time temperature of the optical temperature sensor based on the intensity ratio and a preset intensity ratio-temperature function. The intensity ratio-temperature function is obtained by fitting experimental data after conducting several optical temperature sensing experiments on the silicon carbide color center.

[0032] Furthermore, the laser emitting module emits a laser of a preset wavelength towards the optical temperature sensor, including:

[0033] The laser is coupled using a single-mode fiber and the laser is passed through a lens to form parallel light.

[0034] The parallel light is focused onto the optical temperature sensor using an air objective lens with a preset numerical aperture.

[0035] In one possible implementation, the acquisition module acquires the Stokes fluorescence and anti-Stokes fluorescence reflected by the optical temperature sensor, including:

[0036] The fluorescence reflected by the optical temperature sensor is obtained through the objective lens;

[0037] The fluorescence was split into Stokes fluorescence and anti-Stokes fluorescence using a beam splitter and emitted in different directions.

[0038] The Stokes fluorescence is obtained using a first filter, and the anti-Stokes fluorescence is obtained using a second filter, wherein the transmittance wavelengths of the first filter and the second filter are different.

[0039] In one possible implementation, the intensity ratio calculation module calculates the intensity ratio of the Stokes fluorescence and the anti-Stokes fluorescence based on the photon counts corresponding to the Stokes fluorescence and the anti-Stokes fluorescence, including:

[0040] Based on the detector's sensitivity to the spectrum, different detectors are used to perform spectral measurements on the Stokes fluorescence and anti-Stokes fluorescence respectively, and the corresponding photon counts are obtained.

[0041] The intensity ratio of the Stokes fluorescence and the anti-Stokes fluorescence is calculated based on the corresponding photon counts.

[0042] Furthermore, the temperature calculation module calculates the real-time temperature of the optical temperature sensor based on the intensity ratio and a preset intensity ratio-temperature function, using the following formula:

[0043]

[0044] Where y is the intensity ratio, T is the real-time temperature of the optical temperature sensor, T0 is the initial temperature of the optical temperature sensor, a, b, and c are parameters obtained by fitting experimental data after conducting several optical temperature sensing experiments on the silicon carbide color center, and e is the natural base. Attached Figure Description

[0045] Figure 1 : A schematic flowchart of an embodiment of a quantum all-optical temperature sensing method based on silicon carbide color centers provided by the present invention.

[0046] Figure 2 : A schematic diagram of the structure of a silicon carbide color center, which is an embodiment of a quantum all-optical temperature sensing method based on silicon carbide color centers provided by the present invention.

[0047] Figure 3 : A schematic diagram of the optical device structure of an embodiment of a quantum all-optical temperature sensing method based on silicon carbide color centers provided by the present invention.

[0048] Figure 4 : A schematic diagram of the color center spectrum of an embodiment of a quantum all-optical temperature sensing method based on silicon carbide color centers provided by the present invention.

[0049] Figure 5 : A schematic diagram of a temperature-changing device according to an embodiment of a quantum all-optical temperature sensing method based on silicon carbide color centers provided by the present invention.

[0050] Figure 6 This is a schematic diagram illustrating the variation of anti-Stokes fluorescence intensity with temperature in one embodiment of a quantum all-optical temperature sensing method based on silicon carbide color centers provided by the present invention.

[0051] Figure 7 This is a schematic diagram illustrating the variation of Stokes fluorescence intensity with temperature in one embodiment of a quantum all-optical temperature sensing method based on silicon carbide color centers provided by the present invention.

[0052] Figure 8 The fitted curves of the intensity ratio of anti-Stokes fluorescence and Stokes fluorescence as a function of temperature are provided in one embodiment of a quantum all-optical temperature sensing method based on silicon carbide color centers provided by the present invention.

[0053] Figure 9 This is a schematic diagram illustrating the 20-minute fluorescence intensity ratio change of an embodiment of a quantum all-optical temperature sensing method based on silicon carbide color centers provided by the present invention.

[0054] Figure 10 : A schematic diagram of the fitting curve of uncertainty versus integration time for an embodiment of a quantum all-optical temperature sensing method based on silicon carbide color centers provided by the present invention.

[0055] Figure 11 : A schematic diagram of various indicators when different color centers and quantum dots, including this invention, are used for temperature sensing with different observation indicators.

[0056] Figure 12 : A schematic diagram of an embodiment of a quantum all-optical temperature sensing system based on silicon carbide color centers provided by the present invention. Detailed Implementation

[0057] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0058] It should be noted that the step numbers in this document are only for the convenience of explaining the specific embodiments and are not intended to limit the order in which the steps are performed. In the description of this application, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature specified as "first" or "second" may explicitly or implicitly include one or more of that feature.

[0059] Throughout this specification, color centers refer to defective sites in a crystal that selectively absorb visible light. In some crystals, when the energy required for electron transitions at defective sites decreases to a level comparable to that required for visible light, these defective sites create selective absorption surfaces that impart color to the crystal. These defective sites that selectively absorb visible light are called color centers. Defects generally include the absence or replacement of atoms in the crystal lattice. The electronic structure at the defect site changes; for example, when one or two silicon atoms are lost from the silicon carbide lattice, its electronic structure changes. When a color center is excited by a specific external laser, electrons transition to higher energy levels. When an electron transitions to a lower energy level, it releases energy in the form of photons; this is photoluminescence of the color center.

[0060] Example 1:

[0061] like Figure 1 As shown, Example 1 provides a quantum all-optical temperature sensing method based on silicon carbide color centers, including steps S1-S4:

[0062] Step S1: Emit a laser of a preset wavelength to the optical temperature sensor, wherein the optical temperature sensor is composed of silicon carbide color centers;

[0063] Step S2: Obtain the Stokes fluorescence and anti-Stokes fluorescence reflected by the optical temperature sensor;

[0064] Step S3: Calculate the intensity ratio of the Stokes fluorescence and the anti-Stokes fluorescence based on the photon counts corresponding to each of the Stokes fluorescence and the anti-Stokes fluorescence.

[0065] Step S4: Calculate the real-time temperature of the optical temperature sensor based on the intensity ratio and the preset intensity ratio-temperature function. The intensity ratio-temperature function is obtained by fitting experimental data after conducting several optical temperature sensing experiments on the silicon carbide color center.

[0066] Currently, the most studied 4H-silicon carbide color centers are two types: silicon vacancy color centers and double vacancy color centers. Schematic diagrams of these two types of color centers are shown below. Figure 2As shown. A silicon vacancy color center lacks a silicon atom. Based on the two equivalent positions of the silicon atom at the quasi-cubic lattice point k and the hexagonal lattice point h, V1 and V2 are formed respectively. A double vacancy center is composed of adjacent carbon and silicon vacancies. Since carbon and silicon atoms each have two inequivalent positions, there are four types of double vacancy structures composed of adjacent carbon and silicon vacancies: hh, kk, hk, and kh. In the silicon vacancy color center structure, the zero-phonon lines of silicon vacancies V1 and V2 are 862 nm and 917 nm respectively, therefore, they are usually excited by lasers around 780 nm. In the double vacancy color center structure, the zero-phonon line of the silicon carbide double vacancy color center is in the range of 1038 nm to 1133 nm, therefore, it is usually excited by light around 920 nm. When the laser photon energy used for excitation is greater than the fluorescence energy, it is called Stokes excitation. Conversely, when the energy of the excitation photon is lower than that of the fluorescence photon, it is called anti-Stokes excitation. Under anti-Stokes excitation, the phonon energy increases and is absorbed by the photon, causing the silicon vacancy to emit fluorescence at a frequency higher than that of the absorbed photon. In this embodiment, as... Figure 2 As shown, by emitting a continuous 980nm laser at the color center of silicon carbide, it is possible to simultaneously excite silicon vacancy fluorescence (i.e., anti-Stokes excitation) and double vacancy fluorescence (i.e., Stokes excitation) in 4H-silicon carbide.

[0067] This invention provides a quantum all-optical temperature sensing method based on silicon carbide color centers. When a color center is excited by a specific external laser, electrons transition to higher energy levels. When an electron transitions to a lower energy level, it releases energy in the form of photons; this is photoluminescence of the color center. This invention utilizes this characteristic of color centers to construct an optical temperature sensor composed of silicon carbide color centers. Stokes fluorescence and anti-Stokes fluorescence of the optical temperature sensor are excited by a preset laser. Since the intensity of both Stokes fluorescence and anti-Stokes fluorescence follows an Arrhenius exponential relationship with temperature, by collecting these two types of fluorescence and calculating the fluorescence intensity ratio using the photon counts corresponding to each fluorescence, the real-time temperature of the optical temperature sensor can be calculated based on the fluorescence intensity ratio. This achieves all-optical temperature measurement based on silicon carbide color centers. This invention utilizes dual fluorescence intensity to calculate temperature, which has higher accuracy compared to single fluorescence methods. Subsequent experiments demonstrate that, compared to existing technologies, the temperature sensing method provided by this invention has higher sensitivity and stability.

[0068] Furthermore, in step S1, emitting a laser of a preset wavelength to the optical temperature sensor includes:

[0069] The laser is coupled using a single-mode fiber and the laser is passed through a lens to form parallel light.

[0070] The parallel light is focused onto the optical temperature sensor using an air objective lens with a preset numerical aperture.

[0071] This embodiment of the invention further describes the specific process of laser emission. First, a laser is coupled through a single-mode fiber, and then converted into parallel light through a lens. Finally, the parallel light is focused onto the optical temperature sensor through an air objective lens with a preset numerical aperture, thus achieving the excitation of silicon carbide color centers using laser light. In specific application scenarios, the optical temperature sensor can be pre-attached to the surface of the object to be measured, and a corresponding laser emission device can be constructed based on the laser emission method provided in this embodiment. When it is necessary to measure the temperature of the object, the laser emission device emits a laser towards the optical temperature sensor, achieving non-contact temperature measurement and improving the convenience of temperature measurement.

[0072] In one possible implementation, step S2, acquiring the Stokes fluorescence and anti-Stokes fluorescence reflected by the optical temperature sensor, includes:

[0073] The fluorescence reflected by the optical temperature sensor is obtained through the objective lens;

[0074] The fluorescence was split into Stokes fluorescence and anti-Stokes fluorescence using a beam splitter and emitted in different directions.

[0075] The Stokes fluorescence is obtained using a first filter, and the anti-Stokes fluorescence is obtained using a second filter, wherein the transmittance wavelengths of the first filter and the second filter are different.

[0076] This invention provides a method for obtaining Stokes fluorescence and anti-Stokes fluorescence. After the optical temperature sensor is excited by a laser, the optical temperature sensor will radiate fluorescence along a path opposite to that of the laser. Therefore, the fluorescence reflected by the optical temperature sensor can be accurately obtained through an objective lens along the path of laser emission. Then, a beam splitter is used to split the fluorescence into Stokes fluorescence and anti-Stokes fluorescence, which are emitted in different directions. The Stokes fluorescence and anti-Stokes fluorescence are then obtained through different filters in the different directions, thus preparing data for subsequent temperature calculations.

[0077] In one possible implementation, step S3, calculating the intensity ratio of the Stokes fluorescence and the anti-Stokes fluorescence based on the photon counts corresponding to the respective Stokes fluorescence and anti-Stokes fluorescence, includes:

[0078] Based on the detector's sensitivity to the spectrum, different detectors are used to perform spectral measurements on the Stokes fluorescence and anti-Stokes fluorescence respectively, and the corresponding photon counts are obtained.

[0079] The intensity ratio of the Stokes fluorescence and the anti-Stokes fluorescence is calculated based on the corresponding photon counts.

[0080] In this embodiment of the invention, after acquiring the Stokes fluorescence and anti-Stokes fluorescence, the spectra of the Stokes fluorescence and anti-Stokes fluorescence are measured using different detectors to obtain the corresponding photon counts, and then the intensity ratio of the Stokes fluorescence and the anti-Stokes fluorescence is calculated. By calculating the intensity ratio of the two fluorescences, the intensity data of Stokes fluorescence and anti-Stokes fluorescence can be effectively utilized. Furthermore, since the intensity of both fluorescences follows an Arrhenius exponential relationship with temperature, the intensity ratio data can more accurately fit the temperature change curve of the optical temperature sensor compared to the intensity data of a single fluorescence, resulting in a higher sensitivity and stability for the subsequently constructed intensity ratio-temperature function.

[0081] Furthermore, in step S4, the real-time temperature of the optical temperature sensor is calculated based on the intensity ratio and a preset intensity ratio-temperature function, specifically using the following formula:

[0082]

[0083] Where y is the intensity ratio, T is the real-time temperature of the optical temperature sensor, T0 is the initial temperature of the optical temperature sensor, a, b, and c are parameters obtained by fitting experimental data after conducting several optical temperature sensing experiments on the silicon carbide color center, and e is the natural base.

[0084] In a preferred embodiment, by means of Figure 3 The optical device shown implements the quantum all-optical temperature sensing method based on silicon carbide color centers provided by this invention. Figure 3 First, a 980nm laser is coupled to a near-confocal microscope system using a single-mode fiber. Then, a BS 50:50 lens (Thorlabs, AC064-015-B-ML) is used to convert the laser into nearly parallel light. Finally, an air objective lens (OLYMPUS, LCPlan N, 50×) with a numerical aperture of 0.65 is used to focus the laser onto an optical temperature sensor composed of silicon carbide color centers. This optical temperature sensor is placed on a three-dimensional piezoelectric positioning stage. Stokes fluorescence and anti-Stokes fluorescence emitted from the P611.3S and the piezoelectric controller (Digital Piezo Controller, E727.3SD) are collected by the air objective. The air objective directs these two types of fluorescence to a 50:50 beam splitter (BS), causing them to be emitted in different directions. The Stokes fluorescence and anti-Stokes fluorescence are filtered using a 1000 nm long-pass filter (Thorlabs, FELH1000) and a 950 nm short-pass filter, respectively. Finally, based on the detector's spectral sensitivity, the photon counts of the Stokes fluorescence and anti-Stokes fluorescence are measured using a superconducting nanowire single-photon detector (SNSPD) and a single-photon avalanche photodiode (APD), respectively, and the intensity ratio is obtained. The real-time temperature of the optical temperature sensor is then calculated based on the intensity ratio. Compared with existing technologies, the optical device combined with the method of the present invention reduces many unnecessary components, occupies less space, is easy to build and optimize, can improve fluorescence collection efficiency, facilitates the detection of color centers with various emission intensities, and also facilitates the application of color centers to high-sensitivity temperature sensing.

[0085] Furthermore, the method provided by this invention is better compatible with the CMOS field. In the CMOS field, various temperature sensors are needed to know the specific temperature of the chip. Since silicon carbide is widely used in various devices and silicon carbide itself has various color centers, the method proposed in this invention can be used to measure the real-time temperature of silicon carbide devices using all-optical methods, without the need to set up a separate temperature sensor for each silicon carbide device. Alternatively, silicon carbide can be introduced as a companion temperature sensor during the chip manufacturing process.

[0086] Furthermore, in order to construct the intensity ratio-temperature function described in step S4, a series of optical experiments are required on the silicon carbide color centers. The first step is to determine the optical properties of the silicon carbide color centers; spectral measurement is an important means of characterizing color centers. Figure 4 These are the spectra of two color centers measured at room temperature using a 980nm laser excitation. Due to the interaction of electrons and surrounding phonons at room temperature, the spectra will broaden to some extent, forming phonon sidebands. Figure 4 As can be seen, the anti-Stokes spectrum of silicon vacancies covers 846 nm to 950 nm, while the Stokes spectrum of double vacancies covers 1000 nm to 1400 nm. The measurement results are consistent with the optical properties of silicon vacancies and double vacancies. The uneven cutoff at 950 nm and 1000 nm in the figure is caused by the suppression of laser light and uncorrelated fluorescence by the filter. Figure 4 It can be seen that the Stokes fluorescence of double vacancies is much stronger than that of silicon vacancies, which is consistent with the expectation that the anti-Stokes excitation efficiency is lower.

[0087] To investigate the correlation between the fluorescence intensity of anti-Stokes excitation and Stokes excitation of dual-vacancy colors in silicon carbide and the real-time temperature of silicon carbide, this embodiment uses the following... Figure 5 The variable-temperature device shown is used for variable-temperature optical experiments. Figure 5 The left half of the diagram shows the structural schematic, and the right half shows the physical schematic. We used a Single-Stage TEC Element to uniformly heat the sample and control the heating rate. The silicon carbide sample was attached to a ceramic sheet, and a voltage was applied to the TEC module to transfer heat to the sample, changing its temperature. A standard temperature sensor (platinum resistance temperature detector TH100PT) was installed on the silicon carbide sample to detect its real-time temperature, facilitating adjustments to the applied voltage. During the experiment, we excited the silicon carbide sample with a 1mW 980nm laser, increasing the temperature from 296K to 463K. We measured the fluorescence intensity changes of silicon vacancy centers and double vacancy centers with temperature, and also measured the corresponding intensity ratio of anti-Stokes fluorescence to Stokes fluorescence. The experimental results are as follows: Figures 6-8 As shown, where, Figure 6 The fluorescence intensity of silicon vacancy color centers under anti-Stokes excitation as a function of temperature is shown. We found that the anti-Stokes fluorescence intensity and temperature follow an Arrhenius-type exponential relationship. The measured data are consistent with the data... Where k B is the Boltzmann constant, and hΔω is the energy difference between the excitation light and silicon vacancy emission fluorescence (ZPL). Based on the fitting, we obtain... The wavelength is approximately 1042 nm, which coincides with the zero-phonon line of double vacancies (1038 nm to 1133 nm). This indicates that the anti-Stokes fluorescence intensity exhibits an exponential dependence on temperature, which is the fundamental principle of the quantum all-optical temperature sensing method proposed in this invention. Figure 7 The curves showing the fluorescence intensity of dual-vacancy color centers under Stokes excitation as a function of temperature are presented. Although they also satisfy an Arrhenius-type exponential relationship, their physical meaning remains unexplained and requires further investigation. Therefore, to realize a practical temperature sensor, we chose to use the intensity ratio of anti-Stokes fluorescence to Stokes fluorescence to observe temperature. Figure 8 The intensity ratio-temperature function fitting curves for anti-Stokes fluorescence and Stokes fluorescence are shown. We utilize the exponential function. The data was fitted, and the fitting result is as follows: Figure 8 As shown, the three parameters a, b, and c can be obtained based on the specific experimental values.

[0088] Furthermore, to further verify the stability and sensitivity of the method proposed in this invention, we conducted the following experiments. First, to test the stability of the temperature sensing, we measured the change in the fluorescence intensity ratio over 20 minutes at the same temperature. The experimental results are as follows: Figure 9 As shown in the figure, the fluctuation of the fluorescence intensity ratio is 3.1 × 10⁻⁶. -3 This demonstrates that the method proposed in this invention has high stability. Uncertainty is also an indicator for evaluating temperature sensors. We calculate the uncertainty by changing the integration time of the single-photon detector and the avalanche photodiode, and using the standard deviation of the observed values. Figure 10 It is a fitted curve of uncertainty versus integration time, and the data satisfy σ T =1.19t m -0.5 From this, we can further derive the temperature resolution, which is the smallest change the system can distinguish. It is related to the uncertainty and the integration time. Therefore, the temperature resolution η can be obtained. T =1.19K / Hz -1 / 2 (At 1mW). Besides temperature resolution, relative sensitivity is also a typical indicator of a thermometer. Relative sensitivity O is an observed value measured at a specific temperature; at 300 K, the relative sensitivity is 1.06% K⁻¹. Furthermore, Figure 11 This document lists various indicators for temperature sensing using different color centers and quantum dots under different observation metrics. These indicators are, in order, relative sensitivity, temperature resolution, and CMOS compatibility. The first row lists the indicators for the method provided in this invention; the second row lists the indicators for temperature sensing based on the anti-Stokes and Stokes fluorescence intensity ratio of diamond GeV / SiV; the third row lists the indicators for temperature sensing based on the ZPL intensity of diamond NV centers; and the fourth row lists the indicators for temperature sensing based on changes in CdTe fluorescence lifetime. Figure 11 As can be seen, the method provided by this invention has relatively high sensitivity and excellent performance, and also has valuable CMOS compatibility, which can play a potential role in the field of integrated circuits.

[0089] Example 2:

[0090] Correspondingly, such as Figure 12 As shown, Embodiment 2 provides a quantum all-optical temperature sensing system based on silicon carbide color centers, including a laser emission module 10, an acquisition module 20, an intensity ratio calculation module 30, and a temperature calculation module 40.

[0091] The laser emitting module 10 is used to emit a laser of a preset wavelength to the optical temperature sensor, wherein the optical temperature sensor is composed of silicon carbide color centers.

[0092] The acquisition module 20 is used to acquire the Stokes fluorescence and anti-Stokes fluorescence reflected by the optical temperature sensor;

[0093] The intensity ratio calculation module 30 is used to calculate the intensity ratio of the Stokes fluorescence and the anti-Stokes fluorescence based on the photon counts corresponding to the Stokes fluorescence and the anti-Stokes fluorescence, respectively.

[0094] The temperature calculation module 40 is used to calculate the real-time temperature of the optical temperature sensor based on the intensity ratio and a preset intensity ratio-temperature function. The intensity ratio-temperature function is obtained by fitting experimental data after conducting several optical temperature sensing experiments on the silicon carbide color center.

[0095] Furthermore, the laser emitting module 10 emits a laser of a preset wavelength to the optical temperature sensor, including:

[0096] The laser is coupled using a single-mode fiber and the laser is passed through a lens to form parallel light.

[0097] The parallel light is focused onto the optical temperature sensor using an air objective lens with a preset numerical aperture.

[0098] In one possible implementation, the acquisition module 20 acquires the Stokes fluorescence and anti-Stokes fluorescence reflected by the optical temperature sensor, including:

[0099] The fluorescence reflected by the optical temperature sensor is obtained through the objective lens;

[0100] The fluorescence was split into Stokes fluorescence and anti-Stokes fluorescence using a beam splitter and emitted in different directions.

[0101] The Stokes fluorescence is obtained using a first filter, and the anti-Stokes fluorescence is obtained using a second filter, wherein the transmittance wavelengths of the first filter and the second filter are different.

[0102] In one possible implementation, the intensity ratio calculation module 30 calculates the intensity ratio of the Stokes fluorescence and the anti-Stokes fluorescence based on the photon counts corresponding to the Stokes fluorescence and the anti-Stokes fluorescence, including:

[0103] Based on the detector's sensitivity to the spectrum, different detectors are used to perform spectral measurements on the Stokes fluorescence and anti-Stokes fluorescence respectively, and the corresponding photon counts are obtained.

[0104] The intensity ratio of the Stokes fluorescence and the anti-Stokes fluorescence is calculated based on the corresponding photon counts.

[0105] Furthermore, the temperature calculation module 40 calculates the real-time temperature of the optical temperature sensor based on the intensity ratio and a preset intensity ratio-temperature function, using the following formula:

[0106]

[0107] Where y is the intensity ratio, T is the real-time temperature of the optical temperature sensor, T0 is the initial temperature of the optical temperature sensor, a, b, and c are parameters obtained by fitting experimental data after conducting several optical temperature sensing experiments on the silicon carbide color center, and e is the natural base.

[0108] This invention provides a quantum all-optical temperature sensing system based on silicon carbide color centers. When a color center is excited by a specific external laser, electrons transition to higher energy levels. When an electron transitions to a lower energy level, it releases energy in the form of photons; this is photoluminescence of the color center. This invention utilizes this characteristic of color centers to construct an optical temperature sensor composed of silicon carbide color centers. Stokes fluorescence and anti-Stokes fluorescence of the optical temperature sensor are excited by a preset laser. Since the intensity of both Stokes fluorescence and anti-Stokes fluorescence follows an Arrhenius exponential relationship with temperature, by collecting these two types of fluorescence and calculating the fluorescence intensity ratio using the photon counts corresponding to each fluorescence, the real-time temperature of the optical temperature sensor can be calculated based on the fluorescence intensity ratio. This achieves all-optical temperature measurement based on silicon carbide color centers. This invention utilizes dual fluorescence intensity to calculate temperature, which has higher accuracy compared to single fluorescence methods. Subsequent experiments demonstrate that the temperature sensing method provided by this invention has higher sensitivity and stability compared to existing technologies.

[0109] For a more detailed explanation of the working principle and procedures of this embodiment, please refer to the relevant description in Embodiment 1.

[0110] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above descriptions are merely specific embodiments of the present invention and are not intended to limit the scope of protection of the present invention. In particular, it should be noted that any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention for those skilled in the art.

Claims

1. A quantum all-optical temperature sensing method based on silicon carbide color centers, characterized in that, include: A laser of a preset wavelength is emitted toward an optical temperature sensor, wherein the optical temperature sensor is composed of silicon carbide color centers; Acquire the Stokes fluorescence and anti-Stokes fluorescence reflected by the optical temperature sensor; The intensity ratio of the Stokes fluorescence and the anti-Stokes fluorescence is calculated based on the photon counts corresponding to the Stokes fluorescence and the anti-Stokes fluorescence, respectively. The real-time temperature of the optical temperature sensor is calculated based on the intensity ratio and a preset intensity ratio-temperature function. The intensity ratio-temperature function is obtained by fitting experimental data after conducting several optical temperature sensing experiments on the silicon carbide color center.

2. The quantum all-optical temperature sensing method based on silicon carbide color centers as described in claim 1, characterized in that, The process of emitting a laser of a preset wavelength to the optical temperature sensor includes: The laser is coupled using a single-mode fiber and the laser is passed through a lens to form parallel light. The parallel light is focused onto the optical temperature sensor using an air objective lens with a preset numerical aperture.

3. The quantum all-optical temperature sensing method based on silicon carbide color centers as described in claim 1, characterized in that, The acquisition of Stokes fluorescence and anti-Stokes fluorescence reflected by the optical temperature sensor includes: The fluorescence reflected by the optical temperature sensor is obtained through the objective lens; The fluorescence was split into Stokes fluorescence and anti-Stokes fluorescence using a beam splitter and emitted in different directions. The Stokes fluorescence is obtained using a first filter, and the anti-Stokes fluorescence is obtained using a second filter, wherein the transmittance wavelengths of the first filter and the second filter are different.

4. The quantum all-optical temperature sensing method based on silicon carbide color centers as described in claim 1, characterized in that, The step of calculating the intensity ratio of Stokes fluorescence and anti-Stokes fluorescence based on the photon counts corresponding to each of the Stokes fluorescence and anti-Stokes fluorescence includes: Based on the detector's sensitivity to the spectrum, different detectors are used to perform spectral measurements on the Stokes fluorescence and anti-Stokes fluorescence respectively, and the corresponding photon counts are obtained. The intensity ratio of the Stokes fluorescence and the anti-Stokes fluorescence is calculated based on the corresponding photon counts.

5. The quantum all-optical temperature sensing method based on silicon carbide color centers as described in claim 1, characterized in that, The real-time temperature of the optical temperature sensor is calculated based on the intensity ratio and a preset intensity ratio-temperature function, using the following formula: Where y is the intensity ratio, T is the real-time temperature of the optical temperature sensor, T0 is the initial temperature of the optical temperature sensor, a, b, and c are parameters obtained by fitting experimental data after conducting several optical temperature sensing experiments on the silicon carbide color center, and e is the natural base.

6. A quantum all-optical temperature sensing system based on silicon carbide color centers, characterized in that, It includes a laser emission module, an acquisition module, an intensity ratio calculation module, and a temperature calculation module; The laser emitting module is used to emit laser light of a preset wavelength to the optical temperature sensor, wherein the optical temperature sensor is composed of silicon carbide color centers. The acquisition module is used to acquire the Stokes fluorescence and anti-Stokes fluorescence reflected by the optical temperature sensor; The intensity ratio calculation module is used to calculate the intensity ratio of the Stokes fluorescence and the anti-Stokes fluorescence based on the photon counts corresponding to the Stokes fluorescence and the anti-Stokes fluorescence, respectively. The temperature calculation module is used to calculate the real-time temperature of the optical temperature sensor based on the intensity ratio and a preset intensity ratio-temperature function. The intensity ratio-temperature function is obtained by fitting experimental data after conducting several optical temperature sensing experiments on the silicon carbide color center.

7. The quantum all-optical temperature sensing system based on silicon carbide color centers as described in claim 6, characterized in that, The laser emitting module emits a laser of a preset wavelength to the optical temperature sensor, including: The laser is coupled using a single-mode fiber and the laser is passed through a lens to form parallel light. The parallel light is focused onto the optical temperature sensor using an air objective lens with a preset numerical aperture.

8. The quantum all-optical temperature sensing system based on silicon carbide color centers as described in claim 6, characterized in that, The acquisition module acquires the Stokes fluorescence and anti-Stokes fluorescence reflected by the optical temperature sensor, including: The fluorescence reflected by the optical temperature sensor is obtained through the objective lens; The fluorescence was split into Stokes fluorescence and anti-Stokes fluorescence using a beam splitter and emitted in different directions. The Stokes fluorescence is obtained using a first filter, and the anti-Stokes fluorescence is obtained using a second filter, wherein the transmittance wavelengths of the first filter and the second filter are different.

9. A quantum all-optical temperature sensing system based on silicon carbide color centers as described in claim 6, characterized in that, The intensity ratio calculation module calculates the intensity ratio of the Stokes fluorescence and the anti-Stokes fluorescence based on the photon counts corresponding to the Stokes fluorescence and the anti-Stokes fluorescence, including: Based on the detector's sensitivity to the spectrum, different detectors are used to perform spectral measurements on the Stokes fluorescence and anti-Stokes fluorescence respectively, and the corresponding photon counts are obtained. The intensity ratio of the Stokes fluorescence and the anti-Stokes fluorescence is calculated based on the corresponding photon counts.

10. A quantum all-optical temperature sensing system based on silicon carbide color centers as described in claim 6, characterized in that, The temperature calculation module calculates the real-time temperature of the optical temperature sensor based on the intensity ratio and a preset intensity ratio-temperature function. The specific formula is as follows: Where y is the intensity ratio, T is the real-time temperature of the optical temperature sensor, T0 is the initial temperature of the optical temperature sensor, a, b, and c are parameters obtained by fitting experimental data after conducting several optical temperature sensing experiments on the silicon carbide color center, and e is the natural base.

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