CN110793630A - Superconducting nanowire single photon detection system with impedance matching transmission line - Google Patents

Abstract

The invention provides a superconducting nanowire single-photon detection system with an impedance matching transmission line, comprising: a superconducting nanowire single-photon detector; a 1/4 wavelength impedance matching transmission line, one end of which is connected to the superconducting nanowire single-photon detector ; high-pass filter, one end is connected to one end of the 1/4 wavelength impedance matching transmission line connected to the superconducting nanowire single-photon detector, and the other end is grounded; the first port of the three-port device The first port of the three-port device is impedance matched to 1/4 wavelength One end of the transmission line away from the superconducting nanowire single-photon detector is connected; one end of the current source is connected to the second port of the three-port device; the amplifier, the input end of the amplifier is connected to the third port of the three-port device, and the ground of the amplifier terminal to ground. The invention can realize matching readout of specific frequency signal, realize pulse amplitude amplification, reduce time jitter; can shape and remove low-frequency components in the signal, and improve counting rate and detection rate.

Description

Superconducting nanowire single-photon detection system with impedance-matched transmission line

technical field

The invention belongs to the technical field of light detection, in particular to a superconducting nanowire single-photon detection system with impedance matching transmission lines.

Background technique

Superconducting nanowire single photon detector (SNSPD) is a new type of single photon detection technology developed in the past ten years. Its biggest advantage over semiconductor detectors is its ultra-high detection efficiency and fast response. Speed, negligible dark counts, and extremely low temporal jitter, with a spectral response spanning the visible to infrared. In 2001, the Gol'tsman group of Moscow Normal University first fabricated a 200nm-wide superconducting nanowire with a 5nm-thick NbN ultrathin film, and successfully realized single-photon detection in the visible light to near-infrared band, opening the door to the single-photon detection of superconducting nanowires. A first for photon detectors. Since then, many countries and research groups in Europe, the United States, Russia, Japan, and China have carried out research on SNSPD. After more than ten years of development, the detection efficiency of SNSPD at 1.55μm wavelength has been improved from less than 1% to 90%, far exceeding the detection efficiency of semiconductor SPD. In addition, its excellent performance in dark count, low time jitter, high count rate, etc. has been verified in many application fields. Therefore, the SNSPD with excellent performance near the near-infrared band undoubtedly provides a good tool for applications such as lidar and quantum information.

At present, SNSPD has become a research hotspot in the field of superconducting electronics and single-photon detection, and has effectively promoted the scientific and technological development of quantum information, lidar and other fields. Well-known international research institutions in the field of SNSPD include MIT, JPL, NIST in the United States, NICT in Japan, and MSPU in Russia. At present, the optical fiber communication band is 1550nm, and the device with the highest detection efficiency is developed by NIST in the United States using the ultra-low temperature superconducting material WSi (operating temperature <1K), and the detection efficiency is as high as 93%. The highest detection efficiency of SNSPD has also reached more than 90%. In addition to scientific research institutions, there are currently 6 companies mainly engaged in SNSPD-related technology products in the world.

With the development of SNSPD technology, in recent years, the microwave properties of nanowires are also being explored step by step. On the one hand, it is reflected in the continuous exploration of the nanowire mechanism by researchers;

Existing single-photon detection systems for superconducting nanowires are based on lumped models to analyze and extract waveforms, and do not take into account the impedance matching between the device and the readout. A superconducting nanowire single-photon detection system is based on a high-impedance low-temperature amplifier to achieve improved performance. However, due to the introduction of a high-impedance low-temperature amplifier, the signal amplitude is reduced, thereby reducing the signal-to-noise ratio; at the same time, it will lead to device characterization. The difficulty increases and the system complexity increases. At the same time, it is difficult for the existing single-photon detection systems for superconducting nanowires to achieve comprehensive and excellent performances such as high efficiency, extremely low time jitter, high counts, and practicality.

SUMMARY OF THE INVENTION

In view of the above-mentioned shortcomings of the prior art, the purpose of the present invention is to provide a superconducting nanowire single-photon detection system with an impedance matching transmission line, which is used to solve the existing problems of the superconducting nanowire single-photon detection system in the prior art. Problems such as high time jitter and low count rate, as well as reduced signal-to-noise ratio, difficulty in device characterization, and system complexity.

In order to achieve the above-mentioned purpose and other related purposes, the present invention provides a superconducting nanowire single-photon detection system with impedance matching transmission line, and the superconducting nanowire single-photon detection system with impedance matching transmission line includes:

Superconducting nanowire single-photon detectors;

1/4 wavelength impedance matching transmission line, one end is connected with the superconducting nanowire single photon detector;

a high-pass filter, one end is connected to one end of the 1/4 wavelength impedance matching transmission line connected to the superconducting nanowire single-photon detector, and the other end is grounded;

A three-port device includes a first port, a second port and a third port, and the first port of the three-port device and the 1/4 wavelength impedance matching transmission line are far away from the superconducting nanowire single-photon detector and the One end of the high-pass filter is connected;

a current source, one end of which is connected to the second port of the three-port device;

The amplifier includes an input terminal, an output terminal and a ground terminal; the input terminal of the amplifier is connected to the third port of the three-port device, and the ground terminal of the amplifier is grounded.

Optionally, the equivalent circuit of the superconducting nanowire single-photon detector includes:

Equivalent dynamic inductance, one end is connected with the 1/4 wavelength impedance matching transmission line;

an equivalent resistance, one end of which is connected to one end of the equivalent dynamic inductance away from the 1/4 wavelength impedance matching transmission line, and the other end is grounded;

A switch, one end of which is connected to one end of the equivalent dynamic inductance away from the 1/4 wavelength impedance matching transmission line, and the other end is grounded.

Optionally, the high-pass filter includes:

A filter resistor, one end of which is connected to one end of the 1/4 wavelength impedance matching transmission line;

One end of the filter inductor is connected to one end of the filter resistor away from the 1/4 wavelength impedance matching transmission line, and the other end is grounded.

Optionally, the resistance value of the filter resistor includes 50 ohms; the cut-off frequency of the high-pass filter includes 100 MHz.

Optionally, the three-port device includes:

port resistance, one end is connected with the current source, and the other end is connected with the end of the 1/4 wavelength impedance matching transmission line away from the superconducting nanowire single-photon detector and the high-pass filter;

One end of the port capacitor is connected to one end of the 1/4 wavelength impedance matching transmission line away from the superconducting nanowire single-photon detector and the high-pass filter, and the other end is connected to the input end of the amplifier.

Optionally, the amplifier includes:

an amplifier capacitor, one end of which is connected to the third port of the three-port device;

An amplifier resistor, one end of which is connected to one end of the amplifier capacitor away from the three-port device, and the other end is grounded.

Optionally, the superconducting nanowire single-photon detection system with impedance matching transmission line further includes:

a first coaxial cable, one end of which is connected to one end of the 1/4 wavelength impedance matching transmission line away from the superconducting nanowire single-photon detector and the high-pass filter;

a second coaxial cable, one end of which is connected to one end of the first coaxial cable away from the 1/4 wavelength impedance matching transmission line, and the other end is connected to the first port of the three-port device;

One end of the third coaxial cable is connected to the third port of the three-port device, and the other end is connected to the input end of the amplifier.

Optionally, the impedance of the 1/4 wavelength impedance matching transmission line satisfies the traveling wave matching relationship, so as to realize the connection between the superconducting nanowire single-photon detector and the peripheral readout circuit including the three-port device and the amplifier. Impedance matching.

Optionally, the width of the 1/4 wavelength impedance matching transmission line is determined by the characteristic impedance of the 1/4 wavelength impedance matching transmission line, and the characteristic impedance of the 1/4 wavelength impedance matching transmission line is determined by the single superconducting nanowire. The material and other parameters of the superconducting nanowire in the photon detector are determined; the length of the 1/4 wavelength impedance matching transmission line is determined by the center frequency of the rising edge in the signal transmitted by the 1/4 wavelength impedance matching transmission line, so as to realize the readout of the rising edge of the signal.

As described above, the superconducting nanowire single-photon detection system with impedance matching transmission line of the present invention has the following beneficial effects: the superconducting nanowire single-photon detection system with impedance matching transmission line of the present invention integrates superconducting nanowires on the same chip. Nanowire single-photon detectors and 1/4 wavelength impedance matching transmission lines can achieve matching readout of specific frequency signals (high-frequency components on the rising edge), realize pulse amplitude amplification, and reduce time jitter; by integrating superconductors on the same chip The nanowire single-photon detector and the high-pass filter can shape and remove low-frequency components in the signal, thereby improving the counting rate and detection rate, and greatly improving the overall performance of the superconducting nanowire single-photon detector; the invention has an impedance matching transmission line. The superconducting nanowire single-photon detection system does not require a high-impedance low-temperature amplifier, which can ensure signal amplitude and signal-to-noise ratio, with low characterization difficulty and simple system.

Description of drawings

FIG. 1 shows a circuit diagram of a superconducting nanowire single-photon detection system with impedance matching transmission lines provided by the present invention.

Component label description

10 Superconducting Nanowire Single-Photon Detectors

11 Impedance matching transmission line

12 high pass filter

13 Three-port device

14 Current source

15 Amplifiers

16 chips

17 First coaxial cable

18 Second coaxial cable

19 Third coaxial cable

Detailed ways

The embodiments of the present invention are described below through specific 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 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.

See Figure 1. It should be noted that the diagrams provided in this embodiment are only to illustrate the basic concept of the present invention in a schematic way, although the diagrams only show the components related to the present invention rather than the number, shape and the number of components in actual implementation. For dimension drawing, the shape, quantity and proportion of each component can be arbitrarily changed during actual implementation, and the component layout shape may also be more complicated.

Please refer to FIG. 1 , the present invention provides a superconducting nanowire single-photon detection system with impedance matching transmission lines. The superconducting nanowire single-photon detection system with impedance matching transmission lines includes: a superconducting nanowire single-photon detector 10 1/4 wavelength impedance matching transmission line 11, one end of the 1/4 wavelength impedance matching transmission line 11 is connected with the superconducting nanowire single photon detector 10; high-pass filter 12, one end of the high-pass filter 12 is connected with the The 1/4 wavelength impedance matching transmission line 11 is connected to one end of the superconducting nanowire single-photon detector 10, and the other end of the high-pass filter 12 is grounded; the three-port device 13 includes a third A port, a second port and a third port, the first port of the three-port device 13 and the 1/4 wavelength impedance matching transmission line 11 are far away from the superconducting nanowire single-photon detector 10 and the high-pass filter 12 is connected to one end; current source 14, one end of the current source 14 is connected to the second port of the three-port device 13; amplifier 15, the amplifier 15 includes an input terminal, an output terminal and a ground terminal; the amplifier The input end of 15 is connected to the third port of the three-port device 14, and the ground end of the amplifier 15 is grounded; wherein, the superconducting nanowire single-photon detector 10, the 1/4 wavelength impedance matching transmission line 11 and the high-pass filter 12 are integrated on the same chip 16 . The superconducting nanowire single-photon detection system with impedance matching transmission line of the present invention can be realized by integrating the superconducting nanowire single-photon detector 10 and the 1/4 wavelength impedance matching transmission line 11 on the same chip 16 . Realize the matching readout of specific frequency signals (high-frequency components on the rising edge), realize the amplification of pulse amplitude, and reduce time jitter; by integrating the superconducting nanowire single-photon detector 10 and the high-pass The filter 12 realizes that the low-frequency signal goes to the ground, and can shape and remove the low-frequency components in the signal, thereby improving the counting rate and detection rate, and greatly improving the overall performance of the superconducting nanowire single-photon detector 10; the present invention has impedance matching. The superconducting nanowire single-photon detection system of the transmission line does not require a high-impedance low-temperature amplifier, which can ensure the signal amplitude and signal-to-noise ratio, with low characterization difficulty and simple system.

As an example, the superconducting nanowire single-photon detector 10 may be any existing superconducting nanowire single-photon detector, and its specific structure is not limited herein.

As an example, the equivalent circuit of the superconducting nanowire single-photon detector 10 may include: an equivalent dynamic inductance L1, one end of the equivalent inductance L1 is connected to the 1/4 wavelength impedance matching transmission line 11; an equivalent Resistor R1, one end of the equivalent resistor R1 is connected to one end of the equivalent dynamic inductance L1 away from the 1/4 wavelength impedance matching transmission line 11, and the other end of the equivalent resistor R1 is grounded; switch K, the switch One end of K is connected to one end of the equivalent dynamic inductance L1 away from the 1/4 wavelength impedance matching transmission line 11 , and the other end of the switch K is grounded. Since the superconducting nanowire single-photon detector 10 normally works in the superconducting region, when a photon appears, the superconducting nanowire in the superconducting nanowire single-photon detector 10 becomes a resistance region, which The transition of the resistive region in the superconducting region can be represented by the parallel structure of the equivalent resistance R1 and the switch K; at the same time, the superconducting nanowire is an ultra-thin and ultra-narrow structure, and the generated readout The signal is a radio frequency signal, so its equivalent dynamic inductance L1 is not negligible, so the equivalent circuit of the superconducting nanowire single-photon detector 10 can be as described above.

As an example, the high-pass filter 12 may include: a filter resistor R2, one end of the filter resistor R2 is connected to one end of the 1/4 wavelength impedance matching transmission line 11; a filter inductor L2, one end of the filter inductor L2 is connected to the One end of the filter resistor R2 away from the 1/4 wavelength impedance matching transmission line 11 is connected, and the other end of the filter inductor L2 is grounded. The high-pass filter 12 is used to shape the low-frequency signal in the readout signal generated by the superconducting nanowire, that is, to perform square wave shaping on the readout signal, thereby increasing the count rate.

As an example, the high-pass filter 12 can be selected according to actual needs, but it must be ensured that the high-pass filter 12 can filter out the low-frequency components of the falling edge of the signal and retain the high-frequency components of the rising edge of the signal; preferably, In this embodiment, the cut-off frequency of the high-pass filter 12 includes 100 MHz (for example, 150 MHz), that is, the high-pass filter 12 may be a filter with a cut-off frequency of 100 MHz.

As an example, the filter resistor R2 in the high-pass filter 12 needs to select a resistor with a suitable resistance value to achieve the improvement of the maximum count rate; preferably, in this embodiment, the resistance value of the filter resistor R2 is preferably 50 ohms.

As an example, the three-port device 13 may include: a port inductor L3, one end of the port inductor L3 is connected to the current source 14, and the other end of the port inductor L3 is far away from the 1/4 wavelength impedance matching transmission line 11 The superconducting nanowire single photon detector 10 and one end of the high-pass filter 12 are connected; the port capacitor C1, one end of the port capacitor C1 and the 1/4 wavelength impedance matching transmission line 11 are far away from the superconducting nanowire One end of the line single photon detector 10 and the high-pass filter 12 are connected, and the other end of the port capacitor C1 is connected to the input end of the amplifier 15; the port inductance L3 and the port capacitor C1 are connected with the One end of the 1/4 wavelength impedance matching transmission line 11 that is far away from the superconducting nanowire single-photon detector 10 and one end of the high-pass filter 12 is connected to the first port of the three-port device 13, and the port inductance The end of L3 connected to the current source 14 is the second port of the three-port device 13 ; the end of the port capacitor C1 connected to the amplifier 15 is the third port of the three-port device 13 .

As an example, the first port of the three-port device 13 can allow both DC signals and radio frequency signals to pass through; the second port of the three-port device 13 only allows DC signals to pass through, and the third port of the three-port device 13 Three ports only allow RF signals to pass through. The current source 14 applies a bias current to the superconducting nanowires in the superconducting nanowire single-photon detector 10 via the second port of the three-port device 13, and the radio frequency generated by the superconducting nanowires The signal is processed by the 1/4 wavelength impedance matching transmission line 11 and the high-pass filter 12 and then output to the amplifier 15 through the first port and the third port of the three-port device 13 .

As an example, the amplifier 15 may include: an amplifier capacitor C2, one end of the amplifier capacitor C2 is connected to the third port of the three-port device 13; an amplifier resistor R3, one end of the amplifier resistor R3 is connected to the amplifier capacitor C2 One end away from the three-port device 13 is connected, and the other end of the amplifier capacitor C2 is grounded. The amplifier 15 is used to amplify the radio frequency signal output by the three-port device 13 from about 1 mV to the order of 100 mV for easy readout.

As an example, the superconducting nanowire single-photon detection system with impedance matching transmission line may further include: a first coaxial cable 17 , and one end of the first coaxial cable 17 is far away from the 1/4 wavelength impedance matching transmission line 11 One end of the superconducting nanowire single photon detector 10 and the high-pass filter 12 are connected; a second coaxial cable 18, one end of the second coaxial cable 18 is far away from the first coaxial cable 17. One end of the 1/4 wavelength impedance matching transmission line 11 is connected, and the other end of the second coaxial cable 18 is connected to the first port of the three-port device 13; One end of the coaxial cable 19 is connected to the third port of the three-port device 13 , and the other end of the third coaxial cable 19 is connected to the input end of the amplifier 15 .

Specifically, since the amplifier 15 is preferably an amplifier with standard 50 ohm impedance matching, in this embodiment, the first coaxial cable 17 , the second coaxial cable 18 and the third coaxial cable The coaxial cables 19 are preferably coaxial cables with 50 ohm impedance matching.

Specifically, since the superconducting nanowire itself has high impedance, and the peripheral readout circuit is impedance matching of 50 ohms, the purpose of the 1/4 wavelength impedance matching transmission line 11 is to realize the superconducting nanowire The single-photon detector 10 is matched with the peripheral readout circuit to match and read out a specific frequency signal (such as a high-frequency component of a rising edge) in the readout signal generated by the superconducting nanowire single-photon detector 10 .

More specifically, the impedance of the 1/4 wavelength impedance matching transmission line 11 satisfies the traveling wave matching relationship, so as to realize the superconducting nanowire single photon detector 10 and the first coaxial cable 17, the first The impedances of the second coaxial cable 18 , the third coaxial cable 19 , the three-port device 13 and the peripheral readout circuit of the amplifier 15 are matched.

It should be noted that the traveling wave matching relationship is to obtain the initial characteristic impedance of the 1/4 wavelength impedance matching transmission line 11 (different superconducting nanowires have different parameters such as square inductance) through Sonnet software simulation (that is, the 1/4 wavelength impedance matching the characteristic impedance of the end of the transmission line 11 connected to the superconducting nanowire single-photon detector 10) and the final characteristic impedance of the 1/4 wavelength impedance matching transmission line 11 (that is, the 1/4 The characteristic impedance of the end of the wavelength impedance matching transmission line 11 connected to the first coaxial cable 17) obtains the characteristic impedance of the 1/4 wavelength impedance matching transmission line 11; then, changing the 1/4 wavelength impedance matching transmission line 11 The corresponding characteristic impedance at different widths can be obtained from the width of , and the function of the characteristic impedance changing with the width of the 1/4 wavelength impedance matching transmission line 11 can be obtained by fitting; /4 wavelength impedance matching the width of the transmission line 11 .

As an example, since the length of the 1/4 wavelength impedance matching transmission line 11 determines the center frequency of the signal it passes through, the length of the 1/4 wavelength impedance matching transmission line 11 is determined by the length of the 1/4 wavelength impedance matching transmission line 11 The center frequency of the rising edge in the transmitted signal is determined to realize the readout of the rising edge of the signal.

In summary, the present invention provides a superconducting nanowire single-photon detection system with an impedance matching transmission line, and the superconducting nanowire single-photon detection system with an impedance matching transmission line includes: a superconducting nanowire single-photon detector; A 1/4 wavelength impedance matching transmission line, one end is connected to the superconducting nanowire single photon detector; a high-pass filter, one end is connected to the superconducting nanowire single photon detector with the 1/4 wavelength impedance matching transmission line One end of the three-port device is connected, and the other end is grounded; the three-port device includes a first port, a second port and a third port, and the first port of the three-port device and the 1/4 wavelength impedance matching transmission line are far away from the superconductor The nanowire single-photon detector is connected to one end of the high-pass filter; one end of the current source is connected to the second port of the three-port device; the amplifier includes an input end, an output end and a ground end; The input terminal is connected to the third port of the three-port device, and the ground terminal of the amplifier is grounded. The superconducting nanowire single-photon detection system with impedance matching transmission line of the present invention can realize a specific frequency signal (rising edge high-frequency component) by integrating a superconducting nanowire single-photon detector and a 1/4 wavelength impedance matching transmission line on the same chip. ) matching readout to achieve pulse amplitude amplification and reduce time jitter; by integrating a superconducting nanowire single-photon detector and a high-pass filter on the same chip, the low-frequency components in the signal can be shaped and removed, thereby improving the count rate and detection. speed, greatly improving the overall performance of the superconducting nanowire single-photon detector; the superconducting nanowire single-photon detection system with impedance matching transmission line of the present invention does not require a high-impedance low-temperature amplifier, can ensure signal amplitude and signal-to-noise ratio, and characterize The difficulty is low and the system is simple.

The above-mentioned embodiments merely illustrate the principles and effects of the present invention, but are not intended to limit the present invention. Anyone skilled in the art can modify or change the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or changes made by those with ordinary knowledge in the technical field without departing from the spirit and technical idea disclosed in the present invention should still be covered by the claims of the present invention.

Claims (9)

1. A superconducting nanowire single photon detection system with impedance matched transmission lines, comprising:

a superconducting nanowire single photon detector;

1/4 wavelength impedance matching transmission line, one end of which is connected with the superconducting nanowire single photon detector;

one end of the high-pass filter is connected with one end of the 1/4 wavelength impedance matching transmission line connected with the superconducting nanowire single-photon detector, and the other end of the high-pass filter is grounded;

the three-port device comprises a first port, a second port and a third port, wherein the first port of the three-port device is connected with one end, far away from the superconducting nanowire single photon detector and the high-pass filter, of the 1/4 wavelength impedance matching transmission line;

a current source having one end connected to the second port of the three-port device;

the amplifier comprises an input end, an output end and a grounding end; the input end of the amplifier is connected with the third port of the three-port device, and the grounding end of the amplifier is grounded;

the superconducting nanowire single photon detector, the 1/4 wavelength impedance matching transmission line and the high-pass filter are integrated on the same chip.

2. The superconducting nanowire single photon detection system with impedance matched transmission line of claim 1 wherein the equivalent circuit of the superconducting nanowire single photon detector comprises:

one end of the equivalent dynamic inductor is connected with the 1/4 wavelength impedance matching transmission line;

one end of the equivalent resistor is connected with one end of the equivalent dynamic inductor, which is far away from the 1/4 wavelength impedance matching transmission line, and the other end of the equivalent resistor is grounded;

and one end of the switch is connected with one end of the equivalent dynamic inductor, which is far away from the 1/4 wavelength impedance matching transmission line, and the other end of the switch is grounded.

3. The superconducting nanowire single photon detection system with impedance matched transmission line of claim 1 wherein the high pass filter comprises:

one end of the filter resistor is connected with one end of the 1/4 wavelength impedance matching transmission line;

and one end of the filter inductor is connected with one end of the filter resistor, which is far away from the 1/4 wavelength impedance matching transmission line, and the other end of the filter inductor is grounded.

4. The superconducting nanowire single photon detection system with impedance matched transmission line of claim 3 wherein the resistance of the filter resistor comprises 50 ohms; the cut-off frequency of the high-pass filter comprises hundreds of MHZ.

5. The superconducting nanowire single photon detection system with impedance matched transmission line of claim 1, wherein the three-port device comprises:

one end of the port resistor is connected with the current source, and the other end of the port resistor is connected with one end, far away from the superconducting nanowire single-photon detector and the high-pass filter, of the 1/4 wavelength impedance matching transmission line;

and one end of the port capacitor is connected with one end of the 1/4 wavelength impedance matching transmission line, which is far away from the superconducting nanowire single photon detector and the high-pass filter, and the other end of the port capacitor is connected with the input end of the amplifier.

6. The superconducting nanowire single photon detection system with impedance matched transmission line of claim 1, wherein the amplifier comprises:

one end of the amplifier capacitor is connected with the third port of the three-port device;

and one end of the amplifier resistor is connected with one end of the amplifier capacitor, which is far away from the three-port device, and the other end of the amplifier resistor is grounded.

7. The superconducting nanowire single photon detection system with impedance matched transmission line of claim 1 further comprising:

one end of the first coaxial cable is connected with one end, far away from the superconducting nanowire single-photon detector and the high-pass filter, of the 1/4 wavelength impedance matching transmission line;

one end of the second coaxial cable is connected with one end of the first coaxial cable, which is far away from the 1/4 wavelength impedance matching transmission line, and the other end of the second coaxial cable is connected with the first port of the three-port device;

and one end of the third coaxial cable is connected with the third port of the three-port device, and the other end of the third coaxial cable is connected with the input end of the amplifier.

8. The superconducting nanowire single photon detection system with impedance matched transmission line of any one of claims 1 to 7, wherein the impedance of the 1/4 wavelength impedance matched transmission line satisfies traveling wave matching relationship to achieve impedance matching of the superconducting nanowire single photon detector with peripheral readout circuitry including the three-port device and the amplifier.

9. The superconducting nanowire single photon detection system with impedance matched transmission line of claim 8, wherein the width of the 1/4 wavelength impedance matched transmission line is determined by the characteristic impedance of the 1/4 wavelength impedance matched transmission line, and the characteristic impedance of the 1/4 wavelength impedance matched transmission line is determined by the material of the superconducting nanowire in the superconducting nanowire single photon detector; the length of the 1/4 wavelength impedance matching transmission line is determined by the center frequency of the rising edge in the signal transmitted by the 1/4 wavelength impedance matching transmission line to enable the readout of the rising edge of the signal.

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