A superconducting micron wire single-photon detection device and its preparation method

Abstract

This invention provides a superconducting micron wire single-photon detection device and its fabrication method. By etching the straight portion of the superconducting micron wire, straight groove regions and transition regions of defined width and depth are formed. The etching depth of the straight groove regions is controlled to ensure that the critical current in these regions is lower than that in the corner regions, effectively alleviating the "current crowding effect" caused by the high duty cycle in the corner regions. This invention can improve the quantum efficiency of superconducting micron wires, features a simple structure, a convenient fabrication process, and can be easily expanded to detectors with large photosensitive areas. It has potential applications in quantum optics, laser ranging, dark matter detection, and other fields.

Description

Technical Field

[0001] The present invention relates to the field of photoelectric detection technology, and in particular to a superconducting micron wire single-photon detection device and a preparation method thereof. Background Art

[0002] Superconducting nanowire single-photon detectors (SNSPDs) boast excellent performance, including high detection efficiency, low dark counts, low temporal jitter, and high count rates. They are widely used in fields such as quantum information, bioluminescence imaging, and laser ranging. In recent years, the emerging superconducting micrometer-wire single-photon detector (SMSPD) has expanded the width of the superconducting wire from approximately 100 nm to several microns, compared to traditional SNSPDs. This allows for a larger photosensitive area for the same wire length, enabling detection systems with wider fields of view. SMSPDs with high photosensitivity hold promise for applications in quantum optics, lidar, dark matter detection, and deep-space optical communications.

[0003] However, achieving SMSPDs with high detection sensitivity (quantum efficiency, QE) and high detection efficiency still faces significant challenges. First, conventional SMSPDs still have very low detection sensitivity when detecting photons in the near-infrared band. Second, because the line width of the SMSPD reaches several microns, when the duty cycle is low (generally less than 0.5), most photons will pass directly through the gaps between the superconducting wires without being absorbed, resulting in a significant decrease in the detection efficiency of the SMSPD. When the duty cycle is high (generally greater than 0.5), when the current flows through the bend of the zigzag line, it will concentrate on the inner boundary of the bend, forming the so-called "current crowding effect", which will lead to a decrease in the critical current of the entire device, thereby reducing the detector sensitivity. Moreover, when the SMSPD is operating, the current flowing through the microwire has a certain distribution characteristic in the cross-sectional direction, that is, the current density is higher near the edge of the microwire, while the current density in the center of the microwire is lower. This causes the quantum efficiency of the microwire in detecting photons to be distributed along the cross-sectional direction, with the quantum efficiency in the center region being relatively low.

[0004] In view of this, how to improve the detection sensitivity of SMSPD and solve the "current crowding effect" at the corners has become one of the urgent problems to be solved by those skilled in the art. Summary of the Invention

[0005] The purpose of the present invention is to provide a superconducting micron wire single-photon detection device and a preparation method thereof, which are used to simultaneously solve the problems of the decreased quantum efficiency in the central region of the micron wire of the superconducting micron wire single-photon detector in the prior art and the "current crowding effect" caused by the high duty cycle at the corners, thereby improving the detection sensitivity of the superconducting micron wire single-photon detector.

[0006] To achieve the above-mentioned and other related objectives, the present invention provides a superconducting micron-wire single-photon detection device, which comprises at least:

[0007] A substrate and a superconducting micron-wire formed on the substrate, wherein the superconducting micron-wire includes a plurality of straight portions and bend regions;

[0008] The bend area is connected to the adjacent straight portion end to end in sequence, and the line width of the bend area is not less than the line width of the straight portion. A straight groove area and a transition area are formed on the straight portion. The difference between the length of the straight portion and the sum of the lengths of the straight groove area and the transition area is at least greater than twice the London penetration depth of the superconducting micron wire.

[0009] Optionally, the plurality of straight line portions are arranged in parallel.

[0010] Optionally, the shape of the transition zone is elliptical, and the ratio of the major axis to the minor axis of the transition zone is 1.5-4.

[0011] Optionally, the width of the straight groove zone is greater than half the width of the straight portion, there is a first distance between the upper edge of the straight groove zone and the corresponding upper edge of the straight portion, and there is a second distance between the lower edge of the straight groove zone and the corresponding lower edge of the straight portion, and both the first distance and the second distance are greater than the London penetration depth of the superconducting micron wire.

[0012] Optionally, the straight groove area coincides with a center line of the straight portion, and the first distance and the second distance are equal in size.

[0013] Optionally, the thickness of the straight portion is 3-15 nm, and the depth of the straight groove region is 50%-75% of the thickness of the straight portion.

[0014] The present invention also provides a method for preparing a superconducting micron-wire single-photon detection device, the method comprising at least the following steps:

[0015] S1: providing a substrate and growing a superconducting thin film on a surface of the substrate;

[0016] S2: Spin-coating a photoresist on the superconducting thin film, and performing exposure, development, etching, and photoresist removal to form the superconducting micron-wire, wherein the superconducting micron-wire includes a plurality of straight portions and a curved corner region;

[0017] S3: Spin-coating photoresist on the superconducting micrometer wire again, and forming a straight groove region and a transition region on the straight portion through exposure, development, etching and photoresist removal;

[0018] S4: preparing electrodes on the superconducting microwire.

[0019] Optionally, the thickness of the superconducting film is 3-15 nm, the thickness of the straight portion is 3-15 nm, and the depth of the straight groove region is 50%-75% of the thickness of the straight portion.

[0020] Optionally, the method of forming the superconducting thin film includes a DC magnetron sputtering method.

[0021] Optionally, the material of the superconducting thin film includes one of NbN, Nb, NbSi, WSi, TaN, MoSi or NbTiN.

[0022] As described above, the superconducting micron wire single-photon detection device and the preparation method thereof of the present invention have the following beneficial effects: by forming a straight groove area and a transition area with a certain width and depth on the straight portion, the quantum efficiency of the central region of the superconducting micron wire is improved; since the cross-sectional area of ​​the straight portion becomes smaller, the critical current of the straight portion is reduced and is less than the critical current of the corner region, thereby alleviating the "current crowding effect" caused by the high duty cycle in the corner region, and the elliptical transition zone setting can avoid the current accumulation caused by the sharp change in cross-sectional area at the interface between the right angle portion and the corner region, thereby improving the performance of the single-photon detection device; in addition, the single-photon detection device has the advantages of simple structure and process, and is easier to expand into a detector with a large photosensitive area. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 Shown is a top view schematic diagram of a unit periodic structure of a superconducting micron-wire single-photon detector of the present invention.

[0024] Figure 2 Shown is a three-dimensional schematic diagram of the unit periodic structure of the superconducting micron-wire single-photon detector of the present invention.

[0025] Figure 3 Shown is a side view schematic diagram of a unit periodic structure of a superconducting micron-wire single-photon detector of the present invention.

[0026] Figure 4 Shown is a simulation diagram of the current distribution of the superconducting micron wire in the superconducting micron wire single photon detector of the present invention.

[0027] Figure 5 Shown is a process flow chart of the method for preparing a superconducting micron-wire single-photon detector according to the present invention.

[0028] Figure 6 It is a schematic diagram showing the structure of the superconducting micron wire after forming the present invention.

[0029] Figure 7 It is a schematic diagram showing the structure after the straight groove area is formed according to the present invention.

[0030] Figure 8 The figure shows the AFM scanning results of the straight groove region of the superconducting micron-wire single-photon detector of the present invention.

[0031] Figure 9 Showing the quantum efficiency of superconducting micron-wire single-photon detectors detecting 1550nm photons with and without groove structures.

[0032] Component number description

[0033] 10. Substrate; 11. Superconducting thin film; 12. Superconducting micron wire; 121. Straight portion; 122. Corner region; 13. Straight groove region; 14. Transition region; 141. First distance; 142. Second distance; S1 to S4, steps. DETAILED DESCRIPTION

[0034] The following describes the implementation of the present invention through specific embodiments. People skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification.

[0035] See also Figures 1 to 9 . It should be noted that the structures, proportions, sizes, etc. illustrated in the drawings of this specification are only used to match the contents disclosed in the specification for people familiar with this technology to understand and read, and are not used to limit the limiting conditions for the implementation of the present invention. Therefore, they have no substantive technical significance. Any modification of the structure, change in the proportional relationship or adjustment of the size should still fall within the scope of the technical content disclosed by the present invention without affecting the efficacy and purpose that can be achieved by the present invention. At the same time, the terms such as "upper", "lower", "left", "right", "middle" and "one" quoted in this specification are only for the convenience of description, and are not used to limit the scope of the implementation of the present invention. Changes or adjustments in their relative relationships should also be regarded as the scope of the implementation of the present invention without substantially changing the technical content.

[0036] Example 1

[0037] like Figures 1 to 3 As shown, this embodiment provides a superconducting micron wire single-photon detection device, which includes:

[0038] A substrate 10 and a superconducting micron-wire 12 formed on the substrate 10 , wherein the superconducting micron-wire 12 includes a plurality of straight portions 121 and a bend region 122 ;

[0039] In which, the corner area 122 is connected to the adjacent straight part 121 end to end in sequence and the line width of the corner area 122 is not less than the line width of the straight part 121, and a straight groove area 13 and a transition area 14 are formed on the straight part 121, and the sum of the lengths of the straight groove area 13 and the transition area 14 is less than the length of the straight part 121.

[0040] like Figure 3 As shown, the substrate 10 is located at the bottom of the superconducting micron-wire single-photon detection device.

[0041] Specifically, the substrate 10 includes but is not limited to a silicon substrate, a DBR substrate or a sapphire substrate. As an example, the substrate 10 is a DBR substrate with high reflectivity. An optical film is coated on the surface of the substrate 10 through a polishing process combined with a thermal oxidation process. The optical film is composed of SiO2 and Ta2O5 overlapping with a certain thickness.

[0042] Specifically, the material of the superconducting micron-wire 12 includes, but is not limited to, NbN, Nb, NbSi, WSi, TaN, MoSi, or NbTiN. As an example, the superconducting micron-wire 12 is made of NbN. The thickness of the superconducting micron-wire 12 is set to 3 to 15 nm, and as examples, 3 nm, 9 nm, and 15 nm can be selected. The details are not detailed here.

[0043] Specifically, in this embodiment, the straight portions 121 of the superconducting micron-wire 12 are arranged in parallel, and each corner region 122 has a 180° radius to connect two adjacent straight portions 121. The line width of the corner region 122 is no less than the line width of the straight portions 121. Setting the arc of the corner region 122 to 180° effectively alleviates the current crowding effect in the corner region 122. In actual use, each straight portion 121 can be configured with a certain angle (0° to 180°) as needed, which is not limited here.

[0044] Specifically, in this embodiment, the transition region 14 is elliptical in shape, and the ratio of the major axis to the minor axis of the transition region 14 is 1.5 to 4. The elliptical shape of the transition region 14 avoids current concentration at the interface between the straight portion 121 and the corner region 122 due to the sharp change in cross-sectional area, thereby further alleviating the current crowding effect in the corner region 122. The ratio of the major axis to the minor axis of the transition region 14 is 1.5 to 4, and 1.5, 2, 3, or 4 can be selected as examples, which are not detailed here.

[0045] As an example, the width of the straight groove zone 13 is greater than half the width of the straight portion 121, and there is a first distance 141 between the upper edge of the straight groove zone 13 and the corresponding upper edge of the straight portion 121, and there is a second distance 142 between the lower edge of the straight groove zone 13 and the corresponding lower edge of the straight portion 121. The first distance 141 and the second distance 142 are both greater than the London penetration depth of the superconducting micron wire 12.

[0046] Specifically, in this embodiment, a straight groove region 13 and a transition region 14 are formed on the straight portion 121. The difference between the length of the straight portion 121 and the sum of the lengths of the straight groove region 13 and the transition region 14 is at least greater than twice the London penetration depth of the superconducting micron wire 12, ensuring that the critical currents of the straight groove region 13 and the transition region 14 are sufficiently smaller than the critical current of the corner region 122, thereby avoiding the change in current distribution in the transition region 14 causing the current in the corner region 122 to become more crowded, thereby aggravating the corner crowding effect. The straight groove region 13 serves as the photosensitive region of the single-photon detector. The width of the straight groove region 13 not only affects the light receiving area of ​​the single-photon detector, but also affects the distribution of cross-sectional current density and the current crowding effect in the corner region 122. The width of the straight groove region 13 is set to be greater than half the width of the straight portion 121, so that the detector has a higher duty cycle (generally, when the duty cycle value is greater than 0.5, it can be considered that the duty cycle is high). As the width of the straight groove region 13 increases, the ratio of the current density in the photosensitive region to the maximum current density of the entire line increases. Figure 4 The figure shows the current distribution simulation of the superconducting micron wire 12 in the superconducting micron wire 12 single photon detector of this embodiment. Figure 4 It can be seen that when the duty cycle is high and the straight groove region 13 is not formed on the straight portion 121, a "current crowding effect" occurs in the corner region 122, and the current density in the photosensitive area is much lower than that in the corner region 122, resulting in a decrease in detector performance. After the straight groove region 13 and the elliptical transition region 14 are formed on the straight portion 121, the cross-sectional area of ​​the straight portion 121 is reduced, and the current flux in the straight portion 121 is reduced compared to the current flux in the corner region 122. This reduces the critical current of the straight portion 121 and alleviates the "current crowding effect" in the corner region 122 caused by the high duty cycle. Furthermore, as the width of the straight groove region 13 increases, the ratio of the current density in the photosensitive area to the maximum current density of the entire line also increases, thereby improving the performance of the detector.

[0047] like Figure 1 and Figure 3As shown, a first distance 141 is defined between the upper edge of the straight groove region 13 and the upper edge of the straight portion 121, and a second distance 142 is defined between the lower edge of the straight groove region 13 and the lower edge of the straight portion 121. Both the first distance 141 and the second distance 142 are greater than the London penetration depth of the superconducting microwire 12. The London penetration depth is determined by the properties of the selected superconducting material. This arrangement results in a more concentrated distribution of cross-sectional current density and alleviates current crowding in the bend region 122. As examples, the ratios of the width of the straight groove region 13 to the width of the straight portion 121 are 0.5, 0.6, and 0.8, which are not detailed here.

[0048] Specifically, in this embodiment, the first distance 141 and the second distance 142 are equal in size, that is, the distance between the upper edge of the straight groove area 13 and the upper edge of the straight portion 121 is equal to the distance between the lower edge of the straight groove area 13 and the lower edge of the straight portion 121, so that the center lines of the straight groove area 13 and the straight portion 121 coincide, which can make the current distribution more uniform.

[0049] Specifically, in this embodiment, the thickness of the straight portion 1211 is 3 to 15 nm. Examples of thicknesses include 3 nm, 9 nm, and 15 nm, which are not detailed here. The depth of the straight groove region 13 is 50% to 75% of the thickness of the straight portion 121. Examples of thicknesses include 50%, 60%, 70%, and 75%, which are not detailed here.

[0050] The superconducting micron wire single-photon detection device of this embodiment improves the quantum efficiency of the central region of the superconducting micron wire 12 by forming a straight groove region 13 and a transition region 14 with a certain width on the straight portion 121; and the provision of the straight groove region 13 reduces the cross-sectional area of ​​the straight portion 121 of the superconducting micron wire 12, resulting in a smaller current flux in the straight portion 121 than in the corner region 122, thereby reducing the critical current of the straight portion 121, so that the critical current of the straight portion 121 is lower than the critical value of the corner region 122, alleviating the "current crowding effect" caused by the high duty cycle in the corner region 122, and setting the transition region 14 to an elliptical shape can avoid current concentration caused by a sharp change in cross-sectional area at the interface between the straight portion 121 and the corner region 122, thereby improving the performance of the single-photon detection device; in addition, the single-photon detection device has a simple structure and is easier to expand into a detector with a large photosensitive area.

[0051] Example 2

[0052] like Figure 5 As shown, this embodiment provides a method for preparing a superconducting micron wire single-photon detection device, and the method for preparing a superconducting micron wire single-photon detection device includes at least the following steps:

[0053] S1: providing a substrate 10 and growing a superconducting thin film 11 on the surface of the substrate 10;

[0054] S2: Spin-coating a photoresist on the superconducting thin film 11, and performing exposure, development, etching and photoresist removal to form the superconducting micron-wire 12, wherein the superconducting micron-wire 12 includes a plurality of straight portions 121 and a bend region 122;

[0055] S3: Spin-coating photoresist on the superconducting micron-wire 12 again, and forming a straight groove region 13 and a transition region 14 on the straight portion 121 through exposure, development, etching and photoresist removal;

[0056] S4: preparing electrodes on the superconducting micron-wire 12 .

[0057] As an example, a method of forming the superconducting thin film 11 includes a DC magnetron sputtering method.

[0058] As an example, the material of the superconducting thin film 11 includes one of NbN, Nb, NbSi, WSi, TaN, MoSi or NbTiN.

[0059] Specifically, such as Figure 6 As shown in a, a substrate 10 is first provided. A superconducting thin film 11 for preparing superconducting micron-wires 12 is grown on the surface of the substrate 10 using a high vacuum magnetron sputtering device. The material of the superconducting thin film 11 is NbN and the thickness is set to 3 to 15 nm. In this embodiment, the magnetron sputtering device is powered on to evacuate the vacuum chamber, and argon gas is introduced as a working gas so that the argon gas in the vacuum chamber is maintained at 2×10 -5 Pa, nitrogen gas is introduced as a reaction gas, and the mass flow controller is adjusted so that the partial pressure ratio of Ar:N2 is 30:4. The substrate 10 is moved to just below the Nb target, and the magnetron sputtering DC power supply of the Nb target is turned on. The current parameter is adjusted to 2.19 A, and the sputtering rate is set to 0.8 nm / s. The thickness of the superconducting film 11 is determined by the sputtering rate and sputtering time. Finally, a NbN superconducting film 11 with a thickness of about 12 nm is grown on the substrate 10.

[0060] This embodiment also includes spin coating the surface of the superconducting film 11 with a photoresist of AZ703 at a spin coating speed of 3500 rad / min. The pattern of the superconducting micrometer lines 12 is then formed by laser direct writing. The laser direct writing process first forms a cross for overlay alignment. After development, Ti-Au material is deposited, and the T-Au film other than the cross is peeled off. Specifically, the substrate 10 with the superconducting film 11 grown on the surface is placed in a thermal evaporation coating machine to grow a 5nm thick layer of Ti and a 50nm thick layer of Au. The substrate 10 with the superconducting film 11 grown on the surface is then immersed in an N-methylpyrrolidone solution and placed on a hotplate and heated to 100°C for 1 hour. The gold film on the surface is then gently blown off with a pipette. The substrate is then immersed in acetone and isopropyl alcohol solutions, followed by ultrasonication for 5 minutes, leaving a gold cross mark.

[0061] like Figure 6 As shown in FIG. 2 b, in this embodiment, after forming the golden cross mark, photoresist is again spin-coated on the surface of the substrate 10. The golden cross mark is identified by laser direct writing, and then exposed and developed. Reactive ion etching is then performed to form the superconducting micron wires 12. Specifically, the substrate 10 is placed in an etcher and evacuated. Once the vacuum condition is met, the etching parameters are set. The specific etching parameters are set as follows: CF4 gas is selected, the flow rate is set to 30 sccm, the etching power is selected to 50 mW, the etching time is 39 s, and the etching rate is 0.987 nm / s.

[0062] As an example, the thickness of the straight portion 121 is 3-15 nm, and the depth of the straight groove region 13 is 50%-75% of the thickness of the straight portion 121 .

[0063] like Figure 7As shown, in this embodiment, after etching to form the superconducting micron-wire 12, photoresist is spin-coated again. Laser direct writing is used to identify the gold cross mark for positioning, followed by exposure and development. Reactive ion etching is then performed to form the straight groove region 13 and transition region 14. Since the thickness of the superconducting thin film 11 is 3 to 15 nm, the thickness of the superconducting micron-wire 12 formed is also 3 to 15 nm. Specifically, since the thickness of the oxide layer on the surface of the substrate 10 affects the depth of the groove formed by etching, a test wafer is used to calibrate the etching depth before performing reactive ion etching to form the straight groove region 13 and transition region 14. Furthermore, to ensure more uniform current distribution, the centerline of the formed straight groove region 13 is ensured to coincide with the centerline of the superconducting micron-wire 12 during etching. That is, the distance between the upper edge of the straight groove region 13 and the upper edge of the straight portion 121 is equal to the distance between the lower edge of the straight groove region 13 and the lower edge of the straight portion 121. The depth of the resulting straight groove region 13 is 50% to 75% of the thickness of the straight portion 121. The specific settings of the etching parameters are as follows: CF4 gas is selected, the flow rate is set to 30sccm, the etching power is selected to 40mW, the etching time is 18-22s, and the etching rate is 0.79nm / s. Figure 8 As shown, it shows the AFM scanning result of the straight groove area 13 of the superconducting micron wire 12 single photon detector of the present invention, Figure 8 It can be seen that the surface undulation of the straight groove region 13 formed by the above-set parameters is less than 0.6 nm, and the depth of the groove is about 7 nm.

[0064] Specifically, ultraviolet exposure glue AZ703 is spin-coated on the surface of the superconducting wire, a Ti-Au cross is overlaid by an ultraviolet photolithography machine, the electrode pattern is prepared, and the device electrode is prepared by ion beam etching process. After the preparation is completed, the superconducting micron wire 12 single-photon detector of the present invention is obtained by dicing.

[0065] like Figure 9 Figure 2 shows the quantum efficiency of detecting 1550nm photons using a superconducting micron-wire 12 with and without straight groove regions 13. As can be seen from the figure, the quantum efficiency of the superconducting micron-wire 12 without straight groove regions 13 is approximately 79%, while the quantum efficiency of the superconducting micron-wire 12 increases to 100% after groove etching. Therefore, forming a straight groove region 13 of a certain width on the straight portion 121 can improve the quantum efficiency of the central region of the superconducting micron-wire 12.

[0066] In summary, the present invention provides a superconducting micron wire single-photon detection device and a method for preparing the same. By etching the straight portion of the superconducting micron wire, a straight groove region and a transition region of a certain width and depth are formed on the straight portion, thereby improving the quantum efficiency of the central region of the superconducting micron wire. Furthermore, the formed straight groove region reduces the cross-sectional area of ​​the straight portion of the superconducting micron wire, resulting in a smaller current flux in the straight portion than in the corner region, thereby reducing the critical current of the straight portion, making the critical current of the straight portion lower than the critical value of the corner region, and alleviating the "current crowding effect" caused by the high duty cycle in the corner region. At the same time, the transition region is elliptical, which can avoid current concentration caused by the sharp change in cross-sectional area at the interface between the straight portion and the corner region, thereby improving the performance of the single-photon detection device. Furthermore, the single-photon detection device has a simple structure and can be easily expanded into a detector with a large photosensitive area. Therefore, the present invention effectively overcomes the various shortcomings of the prior art and has high industrial application value.

[0067] 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 skilled in 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 one of ordinary skill in the art without departing from the spirit and technical principles disclosed herein are intended to be covered by the claims of the present invention.

Claims

1. A superconducting micron wire single-photon detection device, characterized in that: The single photon detection device at least comprises: A substrate and a superconducting micron-wire formed on the substrate, wherein the superconducting micron-wire includes a plurality of straight portions and bend regions; In which, the bend area is connected to the adjacent straight part end to end in sequence and the line width of the bend area is not less than the line width of the straight part, a straight groove area and a transition area are formed on the straight part, the difference between the length of the straight part and the sum of the lengths of the straight groove area and the transition area is at least greater than twice the London penetration depth of the superconducting micron wire, the shape of the transition area is elliptical, and the ratio of the major axis to the minor axis of the transition area is 1.5~4, the width of the straight groove area is greater than half of the width of the straight part, there is a first distance between the upper edge of the straight groove area and the corresponding upper edge of the straight part, there is a second distance between the lower edge of the straight groove area and the corresponding lower edge of the straight part, and the first distance and the second distance are both greater than the London penetration depth of the superconducting micron wire.

2. The superconducting micron wire single-photon detection device according to claim 1, characterized in that: The plurality of straight line portions are arranged in parallel.

3. The superconducting micron-wire single-photon detection device according to claim 1, wherein: The first distance and the second distance are equal in size.

4. The superconducting micron wire single-photon detection device according to claim 1, characterized in that: The thickness of the straight portion is 3-15 nm, and the depth of the straight groove region is 50%-75% of the thickness of the straight portion.

5. A method for preparing a superconducting micron wire single-photon detection device, for preparing the superconducting micron wire single-photon detection device according to any one of claims 1 to 4, characterized in that: The preparation method comprises at least the following steps: Providing a substrate, and growing a superconducting thin film on a surface of the substrate; Spin-coating a photoresist on the superconducting thin film, and forming the superconducting micron line by exposure, development, etching and photoresist removal, wherein the superconducting micron line includes a plurality of straight portions and a bend area; Spin-coating photoresist on the superconducting micrometer wire again, and forming a straight groove area and a transition area on the straight portion through exposure, development, etching and photoresist removal; Electrodes are fabricated on the superconducting micron wire.

6. The preparation method according to claim 5, characterized in that: The thickness of the superconducting film is 3-15 nm, the thickness of the straight portion is 3-15 nm, and the depth of the straight groove region is 50%-75% of the thickness of the straight portion.

7. The preparation method according to claim 5, characterized in that: The method of forming the superconducting thin film includes a DC magnetron sputtering method.

8. The preparation method according to claim 5, characterized in that: The material of the superconducting thin film includes one of NbN, Nb, NbSi, WSi, TaN, MoSi or NbTiN.

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