SNSPD-based detection device, detection system and debugging method for preventing SNSPD from being latched

Abstract

The application provides a kind of detection device and detection system based on SNSPD, comprising: SNSPD, amplification module, bias module, impedance matching module and signal processing module;Bias module provides bias current for SNSPD, SNSPD converts optical signal into electrical signal, amplification module receives and amplifies electrical signal, impedance matching module matches the impedance of SNSPD and amplification module, signal processing module processes the amplified electrical signal.The application also provides a kind of debugging method for preventing SNSPD latch, first, the output impedance of SNSPD and the input impedance of amplification module are obtained, second, the impedance of impedance matching module is adjusted, so that the output impedance and the input impedance are matched, finally, the performance of SNSPD output electrical signal is optimized, and the optimal impedance of each part in impedance matching module is obtained.Therefore, the application effectively solves the problems of easy latching, serious reflection and working current loss when the amplifier is connected with SNSPD at close range.

Description

Technical Field

[0001] This invention relates to the field of superconducting detection, and in particular to a detection device, detection system, and debugging method for preventing SNSPD latch-up based on superconducting non-superconducting detection devices (SNSPDs). Background Technology

[0002] Superconducting nanowire single-photon detectors (SNSPDs) are widely used in quantum communication and optical quantum information fields due to their high detection efficiency, low dark count rate, and excellent time resolution. The pulse signal output by an SNSPD has extremely low energy (approximately -50 dBm) before amplification and contains abundant high-frequency components. To ensure signal fidelity and low timing jitter, the readout link typically employs a low-noise amplifier, where the amplifier's noise characteristics determine the system's signal-to-noise ratio.

[0003] To reduce timing jitter and signal transmission loss, researchers have increasingly explored placing low-noise amplifiers closer to the detector chip in cryogenic stages (e.g., 40 K or even 2 K) in high-performance SNSPD systems in recent years. Typically, the first-stage cryogenic amplifier is located in the 40 K temperature range, and its input impedance mismatch can cause reflections in the SNSPD output pulses, thus reducing the maximum biasable current and maximum count rate. As system timing jitter parameters approach physical limits, researchers have begun exploring placing the amplifier even closer to the SNSPD's cold stage (around 2 K) to reduce operating temperature noise, shorten the signal path, and improve the transmission signal-to-noise ratio. However, when the amplifier is directly connected to the SNSPD, the frequency dependence of its input impedance increases significantly. Impedance mismatch with the SNSPD's output impedance can cause signal reflections, triggering SNSPD latch-up, limiting the SNSPD's maximum operating current, and reducing system stability.

[0004] Therefore, how to provide a detection device, detection system, and debugging method for preventing SNSPD latch-up based on SNSPD, while achieving high signal-to-noise ratio, low time jitter, and stable operation, has become one of the technical problems that urgently need to be solved by those skilled in the art.

[0005] It should be noted that the above description of the technical background is only for the purpose of providing a clear and complete explanation of the technical solutions of the present invention and facilitating understanding by those skilled in the art. It should not be assumed that the above technical solutions are known to those skilled in the art simply because they have been described in the background section of this invention. Summary of the Invention

[0006] In view of the shortcomings of the prior art described above, the purpose of this invention is to provide a detection device, detection system and debugging method for preventing SNSPD latch-up based on SNSPD, so as to solve the problem of impedance mismatch when the SNSPD and amplifier are too close in the prior art.

[0007] To achieve the above and other related objectives, the present invention provides a detection device based on an SNSPD, comprising at least: an SNSPD, an amplification module, a bias module, an impedance matching module, and a signal processing module; the SNSPD is used to convert optical signals into corresponding electrical signals; the bias module is used to provide bias current to the SNSPD and is connected between the bias voltage and the output terminal of the SNSPD; the impedance matching module is used to match the impedance of the SNSPD and the impedance of the amplification module; the impedance matching module includes a first resistor and a first inductor, which are connected in series between the output terminal of the SNSPD and ground; the amplification module is used to receive and amplify the electrical signal output by the SNSPD module, and the input terminal of the amplification module is connected to the output terminal of the SNSPD; the signal processing module is used to receive and process the electrical signal output by the amplification module and is connected to the output terminal of the amplification module.

[0008] Optionally, the amplification module includes a first amplifier, a first working resistor, and a second working resistor; the input terminal of the first amplifier serves as the input terminal of the amplification module, the output terminal serves as the output terminal of the amplification module, and the ground terminal is grounded; the first working resistor is connected between a first working voltage and the input terminal of the first amplifier; the second working resistor is connected between a second working voltage and the output terminal of the first amplifier.

[0009] Optionally, the first amplifier is an NPN transistor, with its base at the input terminal, collector at the output terminal, and emitter grounded; or, the first amplifier is an N-type field-effect transistor, with its gate at the input terminal, drain at the output terminal, and source grounded.

[0010] Optionally, the amplification module further includes a negative feedback resistor and a negative feedback capacitor; the negative feedback resistor and the negative feedback capacitor are connected in series between the output terminal and the input terminal of the first amplifier.

[0011] Optionally, the amplification module further includes a first microstrip line; the first microstrip line is connected between the ground terminal and the ground wire of the first amplifier.

[0012] Optionally, the distance between the SNSPD and the amplification module is (0cm, 20cm).

[0013] Optionally, the impedance matching module, the bias module, and the amplification module are formed on the same PCB board.

[0014] To achieve the above and other related objectives, the present invention also provides a detection system based on SNSPD, wherein the SNSPD-based detection system includes at least the aforementioned SNSPD-based detection device.

[0015] To achieve the above and other related objectives, the present invention also provides a debugging method for preventing SNSPD latch-up, implemented based on the aforementioned SNSPD-based detection device. The debugging method for preventing SNSPD latch-up includes at least the following steps: S1: enabling the amplification module to receive the electrical signal output by the SNSPD and obtaining the output impedance of the SNSPD and the input impedance of the amplification module; S2: adjusting the first impedance of the impedance matching module until the input impedance matches the output impedance based on the first impedance; under the constraint of the first impedance, adjusting the impedance of each part in the impedance matching module until the performance of the SNSPD output electrical signal is optimized.

[0016] Optionally, in step S1, the amplification module, the SNSPD, the impedance matching module, and the bias module are set in the same temperature range.

[0017] Optionally, in step S2, the first impedance is adjusted until the frequency-impedance curve of the output impedance fits the frequency-impedance curve of the input impedance plus the first impedance within the target frequency band.

[0018] Optionally, in step S2, the parameters used to evaluate the performance of the SNSPD output electrical signal include pulse amplitude, pulse rise slope, and time jitter.

[0019] As described above, the SNSPD-based detection device, detection system, and debugging method for preventing SNSPD latch-up of the present invention have the following beneficial effects:

[0020] 1. The present invention uses a first resistor and a first inductor to perform impedance matching between the SNSPD and the amplification module, which can prevent SNSPD latch-up and reduce the loss of the SNSPD output electrical signal by minimizing the distance between the impedance matching module and the SNSPD, thereby reducing timing jitter and maintaining the magnitude of the operating current.

[0021] 2. By setting a negative feedback resistor and a negative feedback capacitor in the amplification module, the present invention helps to achieve impedance matching and maintain the stable operation of the amplification module over a wide frequency band; by setting a first microstrip line in the amplification module, the high-frequency gain rise of the amplification module can be suppressed, which helps to increase the operational stability of the amplification module.

[0022] 3. By setting the frequency-impedance curve of the amplification module and the impedance matching module, and setting the frequency-impedance curve of the SNSPD, the present invention can achieve impedance matching and obtain the accurate impedance value of the impedance matching module according to the target frequency band.

[0023] 4. By determining the impedance of the impedance matching module and optimizing the performance of the SNSPD output electrical signal, the present invention can obtain the optimal impedance value of each part in the impedance matching module. Attached Figure Description

[0024] Figure 1 The diagram shown is a schematic representation of the SNSPD-based detection device of the present invention.

[0025] Figure 2 This diagram illustrates a comparison of the detection efficiency of the SNSPD-based detection device of the present invention with that of existing technologies.

[0026] Figure 3 The diagram shown is a schematic representation of the SNSPD-based detection system of the present invention.

[0027] Figure 4 The diagram shows a flowchart of the debugging method for preventing SNSPD latching according to the present invention.

[0028] Figure 5 The diagram shows the frequency-impedance curves of the amplification module and impedance matching module of the present invention under different resistance and inductance values.

[0029] Figure 6 The diagram shows the low-temperature S-curves of the SNSPD of the present invention under different resistance and inductance values.

[0030] Figure 7 The diagram shows a pulse diagram and a partial pulse amplification diagram of the SNSPD output electrical signal of the present invention under different resistance and inductance values.

[0031] Figure 8 The diagram shows a measured pulse diagram and a partial pulse amplification diagram of the SNSPD output electrical signal of the present invention under different resistance and inductance values.

[0032] Figure 9 This diagram illustrates a comparison of the time jitter between the SNSPD-based detection device of the present invention and existing technologies.

[0033] Component designation explanation

[0034] 1. Detection device based on SNSPD

[0035] 1aSNSPD

[0036] 1b bias module

[0037] Rbias bias resistor

[0038] Vbias bias voltage

[0039] 1C impedance matching module

[0040] Rp is the first resistor.

[0041] Lp First Inductor

[0042] 1D magnification module

[0043] VBB first operating voltage

[0044] Rb First Working Resistance

[0045] Rf negative feedback resistor

[0046] Cf negative feedback capacitor

[0047] VCC second working voltage

[0048] Rc second working resistor

[0049] Cin first capacitor

[0050] Cout, the second capacitor

[0051] 11 First Microstrip Line

[0052] 1e signal processing module

[0053] 1f Secondary Amplification Module

[0054] 2. Detection system based on SNSPD Detailed Implementation

[0055] The following specific examples illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention.

[0056] Please see Figures 1-9 It should be noted that the illustrations provided in this embodiment are only schematic representations of the basic concept of the present invention. Therefore, the illustrations only show the components related to the present invention and are not drawn according to the actual number, shape and size of the components in the actual implementation. In the actual implementation, the form, quantity and proportion of each component can be arbitrarily changed, and the layout of the components may also be more complex.

[0057] Traditional methods primarily focus on amplifier noise optimization or current source stability, lacking a joint matching design for the amplifier input impedance and the dynamic characteristics of the SNSPD current. To achieve impedance matching, one circuit design for the amplifier receiving the SNSPD output signal uses a shunt resistor connected in parallel to the SNSPD output at room temperature or low temperature to prevent latch-up. However, due to the shunt effect, the output amplitude decreases, and the output pulse signal-to-noise ratio is significantly reduced, worsening timing jitter.

[0058] Therefore, in order to solve the above-mentioned technical problems, the present invention proposes a detection device, a detection system, and a debugging method for preventing SNSPD latch-up based on SNSPD. The specific technical solution is as follows:

[0059] Example 1

[0060] like Figure 1 As shown, this embodiment provides a detection device 1 based on SNSPD, including: SNSPD 1a, amplification module 1d, bias module 1b, impedance matching module 1c and signal processing module 1e.

[0061] like Figure 1 As shown, SNSPD1a is used to convert optical signals into corresponding electrical signals; bias module 1b is used to provide bias current for SNSPD1a and is connected between bias voltage Vbias and the output terminal of SNSPD1a.

[0062] Specifically, in this embodiment, the electrical signal output by SNSPD1a is a transient signal in pulse form, and the bias module 1b can also isolate the pulse signal. Furthermore, the bias current provided by the bias voltage Vbias maintains SNSPD1a in a highly sensitive metastable state, enabling SNSPD1a to convert the optical signal into a measurable electrical signal. As an example, the bias module 1b includes a decoupling capacitor and a bias resistor Rbias, with a resistance value of 100 kiloohms. In practical applications, the specific bias module 1b can be configured as needed, and is not limited to this embodiment.

[0063] like Figure 1 As shown, the impedance matching module 1c is used to match the impedance of SNSPD1a and the impedance of amplification module 1d; the impedance matching module 1c includes a first resistor Rp and a first inductor Lp, which are connected in series between the output terminal of SNSPD1a and the ground wire.

[0064] Specifically, in this embodiment, to reduce transmission loss and timing jitter of the SNSPD-based detection device 1, the amplification module 1d needs to be placed close to the SNSPD 1a. However, this can easily cause SNSPD 1a signal reflection, triggering SNSPD 1a latch-up. Therefore, an impedance matching module 1c is provided in the detection device, allowing the amplification module 1d to perform impedance matching with the SNSPD 1a in cooperation with the impedance matching module 1c, thus avoiding SNSPD 1a latch-up caused by signal reflection and other issues. Further, the impedance matching module 1c includes a first resistor Rp and a first inductor Lp. The first resistor Rp mainly functions for impedance matching in the low-frequency band, providing a discharge circuit for the SNSPD and ensuring the SNSPD maintains a complete waveform. The first inductor Lp is mainly used to match the impedance of the amplification module 1d and the SNSPD in the high-frequency band. As an example, the first resistor Rp is selected as a low-temperature drift thin-film resistor, and the first inductor Lp is selected as a coreless wire-wound inductor. In practical applications, the specific first resistor Rp and first inductor Lp can be set as needed, and are not limited to this embodiment. Furthermore, by setting the first resistor Rp and the first inductor Lp, the operating current of the SNSPD is not only equivalent to or better than that of traditional solutions, such as... Figure 2 As shown, the detection efficiency of SNSPD will not be affected, which is conducive to maintaining the excellent performance of SNSPD.

[0065] like Figure 1 As shown, the amplifier module 1d is used to receive and amplify the electrical signal output by the SNSPD module, and the input terminal of the amplifier module 1d is connected to the output terminal of the SNSPD.

[0066] Specifically, in this embodiment, the amplification module 1d includes a first amplifier, a first working resistor Rb, and a second working resistor Rc; the input terminal of the first amplifier serves as the input terminal of the amplification module 1d, the output terminal serves as the output terminal of the amplification module 1d, and the ground terminal is grounded; the first working resistor Rb is connected between the first working voltage VBB and the input terminal of the first amplifier; the second working resistor Rc is connected between the second working voltage VCC and the output terminal of the first amplifier. Further, the first amplifier is an NPN transistor, with the base of the NPN transistor as the input terminal, the collector as the output terminal, and the emitter grounded; or, the first amplifier is an N-type field-effect transistor, with the gate as the input terminal, the drain as the output terminal, and the source grounded. In practical applications, the specific type of the first amplifier can be selected as needed, and is not limited to this embodiment. Further, as... Figure 1As shown, the amplification module 1d also includes a negative feedback resistor Rf and a negative feedback capacitor Cf. The negative feedback resistor Rf and the negative feedback capacitor Cf are connected in series between the output and input terminals of the first amplifier, which helps to achieve low-noise impedance matching over a wide bandwidth and maintain the stable operation of the amplification module 1d. Furthermore, as... Figure 1 As shown, the amplification module 1d also includes a first microstrip line 11, which is connected between the ground terminal and the ground wire of the first amplifier to suppress high-frequency gain rise of the amplification module. Furthermore, as... Figure 1 As shown, the amplification module 1d also includes a first capacitor Cin and a second capacitor Cout, which are used to couple the electrical signal output by SNSPD1a.

[0067] Specifically, in this embodiment, the distance between the SNSPD and the amplification module 1d is (0cm, 20cm), including but not limited to 1cm, 3cm, 5cm, 10cm, and 15cm. In practical applications, the distance between the SNSPD and the amplification module 1d can be set as needed, and is not limited to this embodiment. Furthermore, to improve the integration of the detection device, the impedance matching module 1c, the bias module 1b, and the amplification module 1d can be formed on the same PCB board. As an example, when both the SNSPD and the amplification module 1d operate at a temperature of 2.4K, the PCB board material can be FR4 substrate, with a board thickness of 0.8mm, a copper thickness of 1 ounce, and an overall size of 23mm*29mm, which facilitates close connection between the SNSPD and the amplification module 1d. In practical applications, the specific type of PCB board can be set as needed, and is not limited to this embodiment.

[0068] like Figure 1 As shown, the signal processing module 1e is used to receive and process the electrical signal output by the amplification module 1d, and is connected to the output terminal of the first amplifier.

[0069] Specifically, in this embodiment, the signal processing module 1e may include an oscilloscope for observing the pulse amplitude of the electrical signal, etc. The signal processing module 1e may also include a counter for observing the detection efficiency of the electrical signal, etc. In practical applications, the specific structure of the signal processing module 1e can be configured as needed, and is not limited to this embodiment. Furthermore, to improve the quality of signal processing, a secondary amplification module 1d is provided between the signal processing module 1e and the amplification module 1d to further amplify the electrical signal output by the SNSPD. As an example, the secondary amplification module 1d includes a low-noise amplifier connected between the output terminal of the amplification module 1d and the input terminal of the signal processing module 1e. In practical applications, the specific structure of the secondary amplification module 1d can be configured as needed, and is not limited to this embodiment.

[0070] It should be noted that by matching the output impedance of the SNSPD and the input impedance of the amplification module 1d through the impedance matching module 1c, this embodiment has the advantages of avoiding SNSPD latch-up problems, reducing the output amplitude reduction caused by parallel branches, small module size, and low input return loss of the amplification module 1d.

[0071] Example 2

[0072] like Figure 3 As shown, this embodiment provides a detection system 2 based on SNSPD, including: a detection device 1 based on SNSPD.

[0073] Specifically, in this embodiment, the SNSPD-based detection system 2 can be applied in fields such as quantum communication, quantum random number generation, or single-photon timing measurement; wherein, the detection system may include the SNSPD-based detection device 1 of Embodiment 1, or other SNSPD-based detection devices 1 that are the same as or similar to the present invention.

[0074] Example 3

[0075] like Figure 4 As shown, this embodiment provides a debugging method to prevent SNSPD latch-up, including the following steps:

[0076] like Figure 4 As shown, in step S1, the amplification module 1d receives the electrical signal output by the SNSPD and obtains the output impedance of the SNSPD and the input impedance of the amplification module 1d.

[0077] Specifically, in this embodiment, in order to coordinate the operation of the amplification module 1d, SNSPD, bias module 1b, and impedance matching module 1c and reduce measurement data errors, the amplification module 1d, SNSPD, bias module 1b, and impedance matching module 1c are placed in the same temperature range. Further, the temperature range is 2K-40K, including but not limited to 2K, 3K, 4K, 5K, 10K, 15K, 20K, 25K, 30K, and 35K. In practical applications, the specific range of the temperature range can be set as needed, and is not limited to this embodiment.

[0078] like Figure 4 As shown, in step S2, the first impedance of the impedance matching module 1c is adjusted until the input impedance matches the output impedance based on the first impedance; under the constraint of the first impedance, the impedances of each part in the impedance matching module 1c are adjusted until the performance of the output electrical signal of SNSPD1a is optimized.

[0079] Specifically, in this embodiment, in order to match the input impedance with the output impedance, the frequency-impedance curve of the output impedance is obtained. Additionally, as... Figure 5As shown, the frequency-impedance curve of the input impedance plus the first impedance is obtained, and the first impedance is adjusted. When the two curves are relatively close (fitted) within the target frequency band, the input impedance is considered to match the output impedance based on the first impedance. In practical applications, the specific matching method of the input and output impedances can be set as needed, and is not limited to this embodiment. Further, as... Figure 6 As shown, after impedance matching between the SNSPD and the amplifier module 1d, the low-temperature S-parameters of the SNSPD output electrical signal also exhibited excellent performance.

[0080] Specifically, in this embodiment, to save resources and time and ensure the accuracy of the results, the SNSPD-based detection device 1 is simulated on a simulation platform. The first impedance is adjusted on the simulation platform using measured data until the input impedance matches the output impedance based on the first impedance. As an example, ADS (Advanced Design System) is selected as the simulation platform, and the SNSPD is simulated using time-varying resistors, time-varying inductors, bondwire models, and coaxial line models to more closely approximate the actual situation of the SNSPD and reduce impedance matching errors. In practical applications, specific simulation methods can be set as needed, and are not limited to this embodiment.

[0081] Specifically, in this embodiment, the impedance matching module 1c includes a first resistor Rp and a first inductor Lp. The first impedance is formed by the actual first resistor Rp and the first inductor Lp. When the resistance value of the first resistor Rp is too small, the waveform integrity of the SNSPD output signal is low; when the resistance value is too large, the discharge capability of the SNSPD is weak, which can easily cause latch-up. When the inductance value of the first inductor Lp is small, the rising edge slope of the output signal is low; when the inductance value is large, it will affect the impedance matching effect. Therefore, it is necessary to obtain the optimal first resistor Rp and the optimal first inductor Lp. Furthermore, under the constraint of the first impedance, by continuously adjusting the specific impedance values ​​of the first resistor Rp and the first inductor Lp, the performance of the SNSPD output signal can be optimized. Furthermore, the parameters used to evaluate the performance of the SNSPD output signal include pulse amplitude, pulse rising edge slope, and time jitter; as an example, such as Figure 7 , Figure 8 and Figure 9 As shown, pulse amplitude, pulse rise slope, and timing jitter are all used to evaluate the performance of the SNSPD output electrical signal. After the first impedance is determined, among different combinations of the first resistor Rp impedance and the first inductor Lp impedance, the impedance combination with the highest pulse amplitude, the largest pulse rise slope, and the smallest timing jitter is selected. In practical applications, the parameters used to evaluate the performance of the SNSPD output electrical signal can be set as needed, and are not limited to this embodiment.

[0082] In summary, the detection device and system based on SNSPD of the present invention include: an SNSPD, an amplification module, a bias module, an impedance matching module, and a signal processing module. The bias module provides bias current to the SNSPD, the SNSPD converts the optical signal into an electrical signal, the amplification module receives and amplifies the electrical signal, the impedance matching module matches the impedance of the SNSPD with that of the amplification module, and the signal processing module processes the amplified electrical signal. The debugging method for preventing SNSPD latch-up of the present invention first obtains the output impedance of the SNSPD and the input impedance of the amplification module; second, it adjusts the impedance of the impedance matching module to match the output impedance and input impedance; and finally, it optimizes the performance of the output electrical signal of the SNSPD to obtain the impedance of each part of the impedance matching module. Therefore, the present invention not only significantly reduces input return loss but also obtains an optimal impedance matching module, effectively solving the problems of device latch-up, severe reflection, and operating current loss that exist when the amplifier and SNSPD are connected at close range. It significantly improves the stability and timing jitter performance of the SNSPD and is suitable for applications such as quantum information processing and single-photon detection. Therefore, this invention effectively overcomes the various shortcomings of the prior art and has high industrial application value.

[0083] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the invention. Any person skilled in the art can 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 those skilled in the art without departing from the spirit and technical concept disclosed in the present invention should still be covered by the claims of the present invention.

Claims

1. A detection device based on SNSPD, characterized in that, The SNSPD-based detection device includes at least: an SNSPD, an amplification module, a bias module, an impedance matching module, and a signal processing module; The SNSPD is used to convert optical signals into corresponding electrical signals. The bias module is used to provide bias current to the SNSPD and is connected between the bias voltage and the output terminal of the SNSPD. The impedance matching module is used to match the impedance of the SNSPD and the impedance of the amplification module; the impedance matching module includes a first resistor and a first inductor, which are connected in series between the output terminal of the SNSPD and the ground wire. The amplification module is used to receive and amplify the electrical signal output by the SNSPD module, and the input terminal of the amplification module is connected to the output terminal of the SNSPD. The signal processing module is used to receive and process the electrical signal output by the amplification module, and is connected to the output terminal of the amplification module.

2. The detection device based on SNSPD according to claim 1, characterized in that: The amplification module includes a first amplifier, a first working resistor, and a second working resistor; The input terminal of the first amplifier serves as the input terminal of the amplification module, the output terminal serves as the output terminal of the amplification module, and the ground terminal is grounded. The first operating resistor is connected between the first operating voltage and the input terminal of the first amplifier; The second operating resistor is connected between the second operating voltage and the output terminal of the first amplifier.

3. The detection device based on SNSPD according to claim 2, characterized in that: The first amplifier is an NPN transistor, with the base of the NPN transistor being the input terminal of the first amplifier, the collector being the output terminal of the first amplifier, and the emitter being grounded; Alternatively, the first amplifier may be an N-type field-effect transistor, with its gate being the input terminal of the first amplifier, its drain being the output terminal of the first amplifier, and its source being grounded.

4. The detection device based on SNSPD according to any one of claims 1-3, characterized in that: The amplification module also includes a negative feedback resistor and a negative feedback capacitor; the negative feedback resistor and the negative feedback capacitor are connected in series between the output terminal and the input terminal of the first amplifier.

5. The detection device based on SNSPD according to any one of claims 1-3, characterized in that: The amplification module further includes a first microstrip line; the first microstrip line is connected between the ground terminal and the ground wire of the first amplifier.

6. The detection device based on SNSPD according to any one of claims 1-3, characterized in that: The distance between the SNSPD and the amplification module is (0cm, 20cm).

7. The detection device based on SNSPD according to any one of claims 1-3, characterized in that: The impedance matching module, the bias module, and the amplification module are formed on the same PCB board.

8. A detection system based on SNSPD, characterized in that, The SNSPD-based detection system includes at least the SNSPD-based detection device as described in any one of claims 1-7.

9. A debugging method for preventing SNSPD latch-up, implemented based on the SNSPD-based detection device according to any one of claims 1-7, characterized in that, The debugging method for preventing SNSPD latch-up includes at least the following steps: S1: Enable the amplification module to receive the electrical signal output by the SNSPD, and obtain the output impedance of the SNSPD and the input impedance of the amplification module; S2: Adjust the first impedance of the impedance matching module until the input impedance matches the output impedance based on the first impedance; under the constraint of the first impedance, adjust the impedance of each part in the impedance matching module until the performance of the SNSPD output electrical signal is optimized.

10. The debugging method for preventing SNSPD latch-up according to claim 9, characterized in that: In step S1, the amplification module, the SNSPD, the impedance matching module, and the bias module are placed in the same temperature range.

11. The debugging method for preventing SNSPD latch-up according to claim 9, characterized in that: In step S2, the first impedance is adjusted until the frequency-impedance curve of the output impedance fits the frequency-impedance curve of the input impedance plus the first impedance within the target frequency band.

12. The debugging method for preventing SNSPD latch-up according to any one of claims 9-11, characterized in that: In step S2, the parameters used to evaluate the performance of the SNSPD output electrical signal include pulse amplitude, pulse rise slope, and time jitter.

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