Superconducting quantum interference device reading circuit, reading method and measuring system

Abstract

The invention provides a reading circuit, a reading method and a measuring system for a superconducting quantum interference device. The reading circuit for the superconducting quantum interference device comprises an amplification module, an integral operation module and a temperature drift suppression module, the amplification module performs low-noise amplification processing on the detection signal and outputs an inter-stage amplification signal; the temperature drift suppression module heats the amplification module to a preset temperature and obtains a compensation voltage signal based on the temperature signal; and the integral operation module performs temperature drift suppression on the inter-stage amplification signal based on the compensation voltage signal and outputs a reading signal. According to the invention, the temperature drift is suppressed in real time in the reading circuit of the superconducting quantum interference device, so that the problems of circuit instability, inaccurate reading and the like caused by the fact that the temperature drift voltage is input into a feedback loop due to the fact that the finally output reading signal contains the temperature drift voltage are solved.

Description

Technical Field

[0001] The present invention relates to the field of superconducting applications, and in particular to a superconducting quantum interference device readout circuit, a readout method and a measurement system. Background Art

[0002] Superconducting Quantum Interference Device (SQUID) is the most sensitive magnetic sensor known so far. The sensitivity of low-temperature SQUID can reach 1fT (1fT = 10 -15 Tesla) level, and the high-temperature SQUID sensitivity can reach 10fT level. It is an important high-end application magnetic sensor, widely used in biomedicine, geophysical exploration and basic research. In the field of geophysical exploration, it can detect the endogenous magnetic signals generated by the earth. High-precision long-term geomagnetic data helps to reveal important signals such as the movement of the earth's internal crust and earthquake signs.

[0003] In order to detect relatively low-frequency signals of the Earth's magnetic field, especially the internal signals of the Earth's magnetic field that change more slowly, the sensor is usually required to have good low-frequency noise to improve the signal-to-noise ratio of the Earth's magnetic field signal. The sources of low-frequency noise include vibration noise and temperature drift noise; vibration noise includes the noise caused by the unnecessary cutting of the Earth's magnetic field by the magnetic sensor due to external physical vibration; temperature drift noise includes both the temperature drift noise of the circuit elements themselves and the temperature drift noise introduced by the ambient temperature of the circuit.

[0004] The existing temperature drift noise suppression method only performs temperature drift compensation processing on the readout signal of the magnetic sensor through software and algorithms in the later stage, but fails to suppress the temperature drift during the process of the magnetic sensor transmitting the signal, resulting in inaccurate reading and even system instability due to the feedback of unnecessary temperature drift voltage in the feedback loop of the readout circuit.

[0005] It should be noted that the above introduction to the technical background is only for the convenience of providing a clear and complete description of the technical solutions of the present application and facilitating the understanding of those skilled in the art. It cannot be considered that the above technical solutions are well known to those skilled in the art simply because they are described in the background technology section of the present application. Summary of the invention

[0006] In view of the shortcomings of the prior art described above, the purpose of the present invention is to provide a superconducting quantum interference device readout circuit, readout method and measurement system, which are used to solve the problem that the prior art only performs temperature drift compensation processing on the readout signal of the magnetic sensor through software debugging and algorithm optimization in the later stage, but fails to suppress the temperature drift in the process of the magnetic sensor transmitting the signal, resulting in the feedback loop of the readout circuit feeding back unnecessary temperature drift voltage, causing inaccurate readout and even system instability.

[0007] To achieve the above-mentioned purpose and other related purposes, the present invention provides a superconducting quantum interference device readout circuit, including: an amplification module, a temperature drift suppression module and an integral operation module;

[0008] The amplification module receives the detection signal output by the superconducting quantum interference device, and is used to amplify the detection signal with low noise and output an inter-stage amplified signal;

[0009] The temperature drift suppression module is connected to the amplification module, and is used to heat the amplification module to a preset temperature, and to collect a temperature signal of the amplification module and obtain a compensation voltage signal based on the temperature signal;

[0010] The integral operation module is connected to the amplification module and the temperature drift suppression module, and performs temperature drift suppression on the inter-stage amplification signal based on the compensation voltage signal and outputs a readout signal.

[0011] Optionally, the temperature drift suppression module includes a temperature acquisition unit, a temperature control unit and a compensation calculation unit;

[0012] The temperature acquisition unit is connected to the amplification module, and is used to acquire the temperature of the amplification module to obtain a temperature signal, and output the temperature signal to the temperature control unit and the compensation calculation unit;

[0013] The temperature control unit is connected to the temperature acquisition unit and the amplification module, and raises the temperature of the amplification module to the preset temperature based on the temperature signal;

[0014] The compensation calculation unit is connected to the temperature acquisition unit and the integral operation module, and is used to store the temperature-voltage fitting function and obtain the compensation voltage signal from the temperature-voltage fitting function based on the temperature signal.

[0015] Optionally, the temperature acquisition unit includes a temperature sensor.

[0016] Optionally, the temperature control unit includes a resistance wire.

[0017] To achieve the above-mentioned object and other related objects, the present invention provides a superconducting quantum interference device readout method, which is implemented based on the above-mentioned superconducting quantum interference device readout circuit, comprising:

[0018] Heating the amplifying module to a preset temperature, collecting a temperature signal of the amplifying module and obtaining a compensation voltage signal based on the temperature signal;

[0019] The temperature drift of the inter-stage amplified signal is suppressed based on the compensation voltage signal and a readout signal is output.

[0020] Optionally, the compensation voltage signal is obtained from the temperature-voltage fitting function based on the temperature signal.

[0021] Optionally, the output voltage of the amplification module at each temperature is collected in advance, and a fitting function between the temperature and the output voltage is obtained based on a fitting algorithm.

[0022] To achieve the above-mentioned object and other related objects, the present invention provides a superconducting quantum measurement system, comprising: a superconducting quantum interference device and the above-mentioned superconducting quantum interference device readout circuit;

[0023] The superconducting quantum interference device is arranged in a low temperature environment, and is used to detect a magnetic field signal and output the detection signal;

[0024] The superconducting quantum interference device readout circuit is connected to the superconducting quantum interference device and is used to amplify and output the detection signal to obtain the readout signal.

[0025] Optionally, when the temperature drift suppression module includes a temperature acquisition unit, a temperature control unit and a compensation calculation unit, the temperature acquisition unit and the temperature control unit are integrally packaged with the amplification module into a packaging structure.

[0026] Optionally, the superconducting quantum measurement system further includes a heat-insulating shell, which is arranged outside the packaging structure.

[0027] As described above, the superconducting quantum interference device readout circuit, readout method and measurement system of the present invention have the following beneficial effects:

[0028] The present invention suppresses temperature drift in real time in a readout circuit of a superconducting quantum interference device, so that the readout signal finally output does not contain a temperature drift voltage, thereby avoiding the problem of circuit instability and inaccurate reading caused by the temperature drift voltage being input into a feedback loop. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 Shown is a schematic diagram of the structure of a superconducting quantum detector.

[0030] Figure 2Shown is a schematic diagram of the framework of the superconducting quantum interference device readout circuit of the present invention.

[0031] Figure 3 Shown is a schematic structural diagram of a superconducting quantum interference device readout circuit of the present invention.

[0032] Figure 4 It is a schematic diagram showing the steps of the superconducting quantum interference device readout method of the present invention.

[0033] Figure 5 Shown is a schematic structural diagram of the superconducting quantum measurement system of the present invention.

[0034] Component number description

[0035] 1 Superconducting quantum detector

[0036] 11 Superconducting Quantum Interference Device

[0037] 12 Flux-locked readout circuit

[0038] 2 Superconducting quantum measurement system

[0039] 21 Superconducting quantum interference device readout circuit

[0040] 211 Amplification Module

[0041] 212 Integral operation module

[0042] 213 Temperature drift suppression module

[0043] 2131 Temperature Acquisition Unit

[0044] 2132 Temperature Control Unit

[0045] 2133 Compensation calculation unit

[0046] 22 Superconducting Quantum Interference Device DETAILED DESCRIPTION

[0047] The following describes the embodiments of the present invention through specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention.

[0048] See also Figure 1 to Figure 5It should be noted that the illustrations provided in this embodiment are only used to illustrate the basic concept of the present invention in a schematic manner, and the drawings only show components related to the present invention rather than being drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component may be changed arbitrarily, and the component layout may also be more complicated.

[0049] Comparative Example

[0050] like Figure 1 A superconducting quantum detector 1 shown includes a superconducting quantum interference device 11 and a flux locking readout circuit 12 .

[0051] The superconducting quantum interference device 11 (Superconducting Quantum Interference Device, SQUID) is an extremely sensitive magnetic flux sensor, which is widely used to measure weak magnetic fields; and the flux locking readout circuit 12 amplifies and outputs the weak signal detected by the SQUID. When the superconducting quantum detector 1 is working, the readout signal V output by the flux locking readout circuit 12 will be fed back to the superconducting quantum interference device 11 based on the negative feedback loop to maintain the SQUID at the optimal working point; this process is called flux locking, which ensures that the response of the SQUID to the measured magnetic field is linear, so as to achieve accurate measurement of changes in the external magnetic field. This negative feedback mechanism enables the SQUID to convert the nonlinear flux-voltage characteristics into a linear output, so that changes in the external magnetic field can be accurately measured. However, the temperature drift in the superconducting quantum detector 1 will cause signal superposition and unstable flux loop, so that the final readout signal V cannot accurately reflect the changes in the magnetic field detected by the superconducting quantum detector 1.

[0052] The temperature drift of the superconducting quantum detector 1 is caused by, on the one hand, the temperature drift introduced by the temperature difference potential inside the metal wire caused by the change of the liquid helium level caused by the evaporation of liquid helium when the superconducting quantum interference device 11 is stored in a liquid helium environment; on the other hand, it is caused by the temperature drift introduced by the amplifier and components inside the flux locking readout circuit 12. The temperature drift causes the final readout signal V to include not only the detection voltage value VB' corresponding to the detection signal B but also the temperature drift voltage V introduced by the temperature drift. T .

[0053] Therefore, in order to obtain the detection voltage value VB' corresponding to the detection signal B, it is necessary to read the temperature drift voltage V T One way to remove the error is to record the relationship between the temperature change and the readout signal V, and offset the error caused by the temperature response from the readout signal V. However, since the superconducting quantum detector 1 will continuously feed back the readout signal V through a negative feedback loop, the temperature drift voltage V TIt is continuously coupled to the flux-locked sensing circuit 12, destroying the stability of the entire circuit system.

[0054] Example

[0055] In order to solve the above problems, this embodiment provides a superconducting quantum interference device readout circuit 21, and sets temperature drift suppression in the superconducting quantum interference device readout circuit 21. By real-time suppression in the superconducting quantum interference device readout circuit 21, the voltage value corresponding to the detected magnetic field is directly output, so as to avoid the final output readout signal V2 including the temperature drift voltage, thereby avoiding the temperature drift voltage from being input into the feedback loop, resulting in circuit instability and inaccurate reading.

[0056] like Figure 2 As shown, a superconducting quantum interference device readout circuit 21 provided in this embodiment includes: an amplification module 211 , an integral operation module 212 and a temperature drift suppression module 213 .

[0057] like Figure 2 As shown, the amplification module 211 is connected to the detection signal V output by the superconducting quantum interference device (SQUID) 11 B , used to convert the detection signal V B The low noise amplification process is performed and the inter-stage amplified signal V1 is output.

[0058] Specifically, in the present embodiment, the amplification module 211 is configured as a low-noise amplifier. The first input terminal and the second input terminal of the low-noise amplifier are respectively connected to the two ends of the superconducting quantum interference device 212 to perform low-noise amplification on the SQUID. In the present embodiment, the amplification module 211 is configured as a low-noise amplifier, which has better low-noise characteristics than when configured as a differential amplifier. Although the differential amplifier can suppress temperature drift by the common-mode suppression characteristic of the differential amplifier, the temperature drift does not exist completely in the common-mode form; at the same time, the noise of the differential amplifier itself is still relatively high. Therefore, the use of a low-noise amplifier during the setting can better utilize the low-noise advantage of the superconducting quantum interference device.

[0059] like Figure 2-Figure 3 As shown, the temperature drift suppression module 213 is connected to the amplification module 211, and is used to heat the amplification module 211 to a preset temperature and collect the temperature signal of the amplification module 211 to obtain a compensation voltage signal.

[0060] Specifically, the temperature drift suppression module 213 includes a temperature acquisition unit 2131 , a temperature control unit 2132 , and a compensation calculation unit 2133 .

[0061] As an example, the temperature control unit 2132 is used to heat the amplification module 211 to a preset temperature.

[0062] In this embodiment, the temperature control unit 2132 includes a resistance wire, and the temperature is increased by pressurizing the resistance wire. In this embodiment, the preset temperature is set to be higher than the temperature of the amplified module 211 after self-heating based on the ambient temperature. It is preferred that the preset temperature is set to be significantly different from the ambient temperature, so that it is difficult for the amplified module 211 to self-heat to reach the temperature.

[0063] It should be noted that the temperature rise in the superconducting quantum interference device readout circuit 21 includes the temperature rise caused by the heating resistor and the temperature rise caused by the self-generated heat in the amplification module 211. In this embodiment, the amplification module 211 is heated and stabilized at a preset temperature by the heating resistor, limiting the fluctuating temperature of the amplification module 211 (including the self-generated heat of the amplification module 211 and the circuit external environment temperature change of the superconducting quantum interference device readout circuit 21). For example, the external environment is set to 25°C, the amplification module 211 is heated to 1°C-2°C, and the preset temperature is set to 50°C. The temperature is then heated by the heating resistor to stabilize it at 50°C, thereby improving the temperature drift suppression effect of the amplification module 211. In this embodiment, it is considered that the detected temperature has reached the preset temperature when it is within the range of 95% to 105% of the preset temperature.

[0064] It should be further explained that, since the superconducting quantum interference device readout circuit 21 still needs to consider the influence of noise such as vibration noise when measuring weak magnetic fields, it is preferred to set the heating resistance wire to heat up to avoid introducing other types of noise interference (such as vibration noise). At the same time, since the preset temperature in this embodiment is higher than the external environment temperature of the amplification module 211, when the temperature is increased by the heating resistance wire, the amplification module 211 as a whole will continuously dissipate heat to the external environment. Therefore, in this embodiment, the temperature of the superconducting quantum interference device readout circuit 21 can be guaranteed to the maximum extent only by heating up, without introducing other cooling methods to adjust the temperature (such as fan cooling, etc.), and further avoiding the introduction of additional noise (such as physical noise that may be caused by fan cooling).

[0065] As an example, the temperature acquisition unit 2131 is connected to the amplification module 211 , and is used to acquire the temperature of the amplification module 211 to obtain a temperature signal T, and output the temperature signal T to the temperature control unit 2132 and the compensation calculation unit 2133 .

[0066] In this embodiment, the temperature acquisition unit 2131 includes a temperature sensor. The temperature sensor senses the temperature of the amplification module 211 in real time (including the temperature of the amplification module 211 and the temperature of the heating resistor) to ensure that the temperature control unit 2132 accurately heats up to the preset temperature and maintains the preset temperature stable. It should be noted that the specific temperature acquisition method is not limited to this embodiment.

[0067] As an example, the compensation calculation unit 2133 is connected to the temperature acquisition unit 2131 and the integral operation module 212, and is used to store the temperature-voltage fitting function. After receiving the temperature signal T, the corresponding compensation voltage signal V is obtained based on the temperature signal and the temperature-voltage fitting function. T '.

[0068] In this embodiment, the temperature control unit 2132 and the compensation calculation unit 2133 are both arranged in the single chip microcomputer, and the output voltage corresponding to the received current ambient temperature is retrieved by the single chip microcomputer and output as the compensation voltage signal VT' to the input end of the subsequent integral operation module, and the integral operation module 212 is used to perform temperature drift compensation suppression. In this embodiment, it is necessary to set the compensation calculation unit 2133 on the basis of the temperature control unit 2132 to ensure that the superconducting quantum interference device readout circuit 21 is compensated based on the same preset temperature to avoid inaccurate compensation.

[0069] like Figure 2-Figure 3 As shown, the integral operation module 212 is connected to the amplification module 211 and the temperature drift suppression module 213, based on the compensation voltage signal V T 'Suppress the temperature drift of the inter-stage amplified signal and output the readout signal.

[0070] Specifically, the first input terminal of the integral operation module 212 is connected to the output terminal of the amplification module 11, and the second input terminal is connected to the output terminal of the temperature drift suppression module 213. T 'Suppress the temperature drift of the inter-stage amplified signal V1 and output the readout signal V2.

[0071] Specifically, the integral operation module 212 is set as an operational amplifier to perform an integral operation on the input inter-stage amplified signal V1 to obtain the readout signal V2. At a preset temperature, the first input terminal of the integral operation module 212 receives the inter-stage amplified signal V1, and the second input terminal receives the corresponding compensation voltage signal V under the preset temperature. T In the process of the integration operation module 212 performing the integration operation on the inter-stage amplified signal V1, the compensation voltage signal V T 'Input to ensure the temperature drift (temperature drift voltage V T ) is effectively suppressed to ensure that the temperature drift voltage is filtered out from the readout signal V2 output from the integral operation module 212, thereby avoiding problems such as system instability and inaccurate reading caused by the readout signal V2 being fed back to the latch loop.

[0072] In this embodiment, the first input terminal of the integral operation module 212 is set as a positive input terminal, and the second input terminal is set as a negative input terminal. The specific setting is not limited to this embodiment.

[0073] It should be noted that the superconducting quantum interference device readout circuit 21 of this embodiment can also adaptively adjust the preset temperature and compensation voltage value V of the temperature drift compensation. T In this embodiment, the preset temperature is adjusted and the adjusted temperature signal T is continuously tracked to obtain the output waveform of the readout signal V2. The waveform is subjected to noise analysis to determine the preset temperature T corresponding to the minimum temperature drift value of the waveform and the compensation voltage value V T ', and detect the magnetic field to be measured in this state to ensure the accuracy of the detected magnetic field.

[0074] like Figure 4 As shown, this embodiment also provides a superconducting quantum interference device readout method, which is implemented based on the above-mentioned superconducting quantum interference device readout circuit, including:

[0075] S1, heating the amplifying module 211 to a preset temperature, collecting the temperature signal T of the amplifying module 211 and obtaining a compensation voltage signal V based on the temperature signal T T '.

[0076] Specifically, based on the temperature signal T, the compensation voltage signal V is obtained from the temperature-voltage fitting function. T '.

[0077] As an example, in a temperature-controlled environment (such as a laboratory environment), the output voltage of the amplification module 211 at various temperatures is collected in advance, and a fitting function between the temperature signal and the output voltage of the amplification module 211 is obtained based on a fitting algorithm, and the fitting function is stored in the compensation calculation unit 2133.

[0078] In this embodiment, in the process of pre-collecting the temperature to obtain the fitting function, the temperature is set to change from -20°C to 50°C, and the output voltage of the temperature sensor and the amplification module 211 are collected at the same time. The collected data is fitted with the temperature signal and the output voltage change using the fitting function of matlab, and the fitting coefficient is written into the single-chip microcomputer. The fitting algorithm includes but is not limited to linear regression, least squares method, gradient descent method, and iterative polynomial fitting algorithm. Any setting that can fit the relationship between the temperature change and the output voltage of the amplification module 211 is within the protection scope of this embodiment.

[0079] For the above compensation voltage signal V T The principle of compensation is further explained: In this embodiment, when the superconducting quantum interference device readout circuit 21 is set to a preset temperature through the temperature control unit 2131, the temperature change can be controlled within a smaller fluctuation range compared to when the temperature control unit 2131 is not set, which is convenient for subsequent compensation voltage signal V T'The temperature drift can be suppressed more accurately, further ensuring the low noise requirement of the superconducting quantum interference readout circuit 21. When suppressing the subsequent temperature drift (temperature drift voltage VT), it is necessary to measure the temperature-voltage fitting function of the superconducting quantum interference device readout circuit 21 in advance in the realization room environment, so as to facilitate the subsequent compensation through the temperature-voltage fitting function to ensure that the final readout signal V2 is accurate.

[0080] S2, based on the compensation voltage signal V T 'Suppress the temperature drift of the inter-stage amplified signal V1 and output the readout signal V2. The specific compensation method has been described in the previous text and will not be repeated here.

[0081] like Figure 5 As shown, this embodiment provides a superconducting quantum measurement system 2, including: a superconducting quantum interference device 22 and the above-mentioned superconducting quantum interference device readout circuit 21.

[0082] like Figure 5 As shown, the superconducting quantum interference device 22 is used to detect the magnetic field signal and output the detection signal V B In this embodiment, the superconducting quantum interference device 22 converts the weak magnetic flux signal into an electrical signal and outputs it. At the same time, due to the working characteristics of the superconducting quantum interference device 21, the superconducting quantum interference device 21 is set in a low temperature environment.

[0083] like Figure 5 As shown, the superconducting quantum interference device readout circuit 21 is connected to the superconducting quantum interference device 22, and is used to detect the signal V B The amplified output is obtained to obtain the readout signal V2.

[0084] Specifically, when the temperature drift suppression module 213 includes a temperature acquisition unit 2131 , a temperature control unit 2132 , and a compensation calculation unit 2133 , the temperature acquisition unit 2131 , the temperature control unit 2132 , and the amplification module 2133 are packaged into a package structure.

[0085] Specifically, the superconducting quantum measurement system 2 also includes a heat-insulating shell; the heat-insulating shell is arranged outside the packaging structure, that is, the temperature acquisition unit 2131, the temperature control unit 2132 and the amplification module 211 are heat-insulated and arranged to control the temperature of the amplification module 211.

[0086] In this embodiment, the temperature acquisition unit 2131 is configured as a temperature sensor, the temperature control unit 2132 is configured as a resistance wire, and the temperature sensor and the resistance wire are configured closely to the outer shell of the amplification module 211. Preferably, after the temperature sensor and the resistance wire are closely configured as a whole with the amplification module 211, they are covered by a heat-insulating shell to simulate an insulating environment to ensure the temperature.

[0087] In summary, the present invention provides a superconducting quantum interference device readout circuit, a readout method and a measurement system, wherein the superconducting quantum interference device readout circuit includes: an amplification module, an integral operation module and a temperature drift suppression module; the amplification module performs low-noise amplification processing on the detection signal and outputs an inter-stage amplified signal; the temperature drift suppression module heats the amplification module to a preset temperature and obtains a compensation voltage signal based on the temperature signal; the integral operation module suppresses the temperature drift of the inter-stage amplified signal based on the compensation voltage signal, and outputs a readout signal. The present invention suppresses temperature drift in real time in the readout circuit of the superconducting quantum interference device, thereby avoiding the problem that the final output readout signal contains a temperature drift voltage, causing the temperature drift voltage to be input into the feedback loop, resulting in circuit instability and inaccurate reading. Therefore, the present invention effectively overcomes the various shortcomings in the prior art and has a high industrial utilization value.

[0088] The above embodiments are merely illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Anyone familiar with the art may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by a person of ordinary skill in the art without departing from the spirit and technical concept disclosed by the present invention shall still be covered by the claims of the present invention.

Claims

1. A superconducting quantum interference device readout circuit, characterized in that: The superconducting quantum interference device readout circuit at least includes: an amplification module, a temperature drift suppression module and an integral operation module; The amplification module receives the detection signal output by the superconducting quantum interference device, and is used to amplify the detection signal with low noise and output an inter-stage amplified signal; The temperature drift suppression module is connected to the amplification module, and is used to heat the amplification module to a preset temperature, and to collect a temperature signal of the amplification module and obtain a compensation voltage signal based on the temperature signal; The integral operation module is connected to the amplification module and the temperature drift suppression module, and performs temperature drift suppression on the inter-stage amplification signal based on the compensation voltage signal and outputs a readout signal.

2. The superconducting quantum interference device readout circuit according to claim 1, characterized in that: The temperature drift suppression module includes a temperature acquisition unit, a temperature control unit and a compensation calculation unit; The temperature acquisition unit is connected to the amplification module, and is used to acquire the temperature of the amplification module to obtain a temperature signal, and output the temperature signal to the temperature control unit and the compensation calculation unit; The temperature control unit is connected to the temperature acquisition unit and the amplification module, and raises the temperature of the amplification module to the preset temperature based on the temperature signal; The compensation calculation unit is connected to the temperature acquisition unit and the integral operation module, and is used to store the temperature-voltage fitting function and obtain the compensation voltage signal from the temperature-voltage fitting function based on the temperature signal.

3. The superconducting quantum interference device readout circuit according to claim 2, characterized in that: The temperature acquisition unit includes a temperature sensor.

4. The superconducting quantum interference device readout circuit according to claim 2, characterized in that: The temperature control unit includes a resistance wire.

5. A superconducting quantum interference device readout method, implemented based on the superconducting quantum interference device readout circuit according to any one of claims 1 to 4, characterized in that: The superconducting quantum interference device readout method at least comprises: Heating the amplifying module to a preset temperature, collecting a temperature signal of the amplifying module and obtaining a compensation voltage signal based on the temperature signal; The temperature drift of the inter-stage amplified signal is suppressed based on the compensation voltage signal and a readout signal is output.

6. The superconducting quantum interference device readout method according to claim 5, characterized in that: The compensated voltage signal is obtained from the temperature-voltage fitting function based on the temperature signal.

7. The superconducting quantum interference device readout method according to claim 6, characterized in that: The output voltage of the amplification module at each temperature is collected in advance, and a fitting function between the temperature and the output voltage is obtained based on a fitting algorithm.

8. A superconducting quantum measurement system, characterized in that: The superconducting quantum measurement system comprises a superconducting quantum interference device and a superconducting quantum interference device readout circuit as claimed in any one of claims 1 to 4; The superconducting quantum interference device is arranged in a low temperature environment, and is used to detect a magnetic field signal and output the detection signal; The superconducting quantum interference device readout circuit is connected to the superconducting quantum interference device and is used to amplify and output the detection signal to obtain the readout signal.

9. The superconducting quantum measurement system according to claim 8, characterized in that: When the temperature drift suppression module includes a temperature acquisition unit, a temperature control unit and a compensation calculation unit, the temperature acquisition unit and the temperature control unit are packaged integrally with the amplification module into a packaging structure.

10. The superconducting quantum measurement system according to claim 9, characterized in that: The superconducting quantum measurement system also includes a heat-insulating shell, which is arranged outside the packaging structure.

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