Josephson parametric amplifier based on a multi-section quarter-wave impedance transformation line

Abstract

The application discloses a Josephson parametric amplifier based on a multi-section quarter-wave impedance transformation line, which comprises input and output ports of the amplifier, a multi-section quarter-wave impedance transformation line, a superconducting Josephson junction nonlinear resonator and a corresponding magnetic flux bias line, wherein the multi-section quarter-wave impedance transformation line is composed of four-section quarter-wave transmission lines, and all of them are prepared by using a planar coplanar waveguide circuit.In addition, the Josephson parametric amplifier is prepared by using a lanthanum aluminate substrate, and compared with common high-resistance silicon or sapphire substrates, the Josephson parametric amplifier has a higher relative dielectric constant, so that the reliability of the preparation process is improved.The application uses the multi-section quarter-wave impedance transformation line to realize impedance matching between the parametric amplifier and the external environment, and innovatively uses the lanthanum aluminate substrate to prepare the parametric amplifier, so that the reliability and yield of the preparation process are effectively improved, and the prepared sample is continuously adjustable in a large frequency range and has excellent gain and bandwidth performance.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of amplifiers, and particularly relates to a Josephson parametric amplifier based on a multi-section quarter-wave impedance transformer line. BACKGROUND

[0002] Superconducting parametric amplifiers based on Josephson junctions have achieved noise performance close to the quantum limit and have proven to be an important tool for superconducting quantum information processing. It has been widely used in single readout, quantum feedback, vacuum squeezed state noise and entangled microwave photon pairs. Although the previously reported Josephson parametric amplifier can provide sufficient gain and noise close to the quantum limit to meet the high-fidelity requirements of quantum information processing, its bandwidth is limited by the bandwidth of the external resonator, resulting in a bandwidth of about tens of megahertz when the gain exceeds 15 dB.

[0003] Among the many schemes currently disclosed, the impedance transformer line mainly adopts two types: the traditional single-section quarter-wave impedance transformer line and the impedance transformer line with a gradual structure. The traditional single-section quarter-wave impedance transformer line is relatively easy to prepare, but can only achieve impedance matching in a fixed and small frequency range; the impedance transformer line with a gradual structure can achieve impedance matching in a larger frequency range, but its structure design is complex and requires high process precision.

[0004] Therefore, there is a need for a Josephson parametric amplifier based on a multi-section quarter-wave impedance transformer line, which has a simple circuit plane design, high chip production yield, can achieve impedance matching in a larger frequency range, and has a bandwidth of several hundred megahertz when the gain is above 15 dB. SUMMARY

[0005] The present application aims to provide a Josephson parametric amplifier based on a multi-section quarter-wave impedance transformer line.

[0006] The technical solution for achieving the present application is as follows: a Josephson parametric amplifier based on a multi-section quarter-wave impedance transformer line, comprising an input / output port, a multi-section quarter-wave impedance transformer line, a superconducting Josephson junction nonlinear resonator, and a magnetic flux bias line; one end of the multi-section quarter-wave impedance transformer line is connected to the input / output port, and the other end is connected to the superconducting Josephson junction nonlinear resonator; the other end of the superconducting Josephson junction nonlinear resonator is connected to the magnetic flux bias line, wherein:

[0007] The multi-section quarter wavelength impedance transformation line comprises a first section of quarter wavelength impedance transformation line, a second section of quarter wavelength impedance transformation line, a third section of quarter wavelength impedance transformation line and a fourth section of quarter wavelength impedance transformation line, all of which are in the form of planar coplanar waveguide transmission lines, and the characteristic impedances of the four sections of quarter wavelength impedance transformation line are respectively Z1, Z2, Z3 and Z4, and the impedances of the input and output ports and the superconducting Josephson junction nonlinear resonator are respectively Z0 and Z L The characteristic impedances of the four sections of quarter wavelength impedance transformation line are determined according to N = 4, wherein N is the number of sections of the multi-section quarter wavelength impedance transformation line.

[0008] Further, the characteristic impedances of the quarter wavelength impedance transformation lines are adjusted by changing the ratio of the width of the center conductor to the width of the gap, and the higher the ratio of the width of the center conductor to the width of the gap, the lower the characteristic impedance of the planar coplanar waveguide transmission line; in addition, the characteristic impedance is also related to the chip substrate material, and under the condition that the ratio of the width of the center conductor to the width of the gap is constant, the greater the relative permittivity of the chip substrate, the lower the characteristic impedance value of the transmission line.

[0009] Further, a lanthanum aluminate substrate with a thickness of 500 μm is used.

[0010] Further, the superconducting Josephson junction nonlinear resonator is composed of a parallel plate capacitor and a nonlinear inductor in parallel, wherein:

[0011] The nonlinear inductor is a direct current superconducting quantum interference device composed of two superconducting Josephson junctions in parallel, the input end of the parallel plate capacitor is connected to the fourth section of quarter wavelength impedance transformation line, and the grounded end of the direct current superconducting quantum interference device is connected to the magnetic flux bias line.

[0012] Further, the working process is as follows:

[0013] The input and output port inputs the microwave signal to be amplified, and after transmission through the multi-section quarter wavelength impedance transformation line, the superconducting Josephson junction nonlinear resonator is inputted;

[0014] The magnetic flux bias line inputs direct current and pump signal, by changing the direct current, the magnetic flux passing through the superconducting quantum interference device is adjusted, the equivalent inductance is changed, and then the working frequency of the superconducting Josephson junction nonlinear resonator is adjusted, the nonlinear inductor of the superconducting Josephson nonlinear resonator is used to realize the mixing between the input pump signal and the signal to be amplified, the energy of the pump signal is converted into the energy required for the input signal amplification, and the amplified signal is reflected along the input transmission line, and is outputted through the input and output port, and the input and output signals are separated through the input and output port and the microwave circulator.

[0015] Further, the input and output port, the multi-section quarter wavelength impedance transformation line and the magnetic flux bias line all adopt niobium film with a thickness of 90nm to 120nm.

[0016] Further, the upper plate of the parallel plate capacitor of the superconducting Josephson junction nonlinear resonator is made of aluminum, the dielectric layer is made of silicon nitride with a thickness of 200nm, and the lower plate is made of niobium.

[0017] Further, the direct current superconducting quantum interference device adopts a three-layer structure Josephson junction of aluminum-aluminum oxide-aluminum.

[0018] Further, the multi-section quarter wavelength impedance transformation line adopts laser direct writing lithography, and the precision limit of the laser direct writing lithography is about 1μm, and the gap width of the planar coplanar waveguide transmission line of the multi-section quarter wavelength impedance transformation line is more than 3μm.

[0019] Further, the center working frequencies of the first section quarter wavelength impedance transformation line, the second section quarter wavelength impedance transformation line, the third section quarter wavelength impedance transformation line and the fourth section quarter wavelength impedance transformation line are the same.

[0020] Compared with the prior art, the Josephson parametric amplifier has the following advantages: 1) the design process is simple, the impedance matching between the environmental impedance 50Ω and the characteristic impedance of the nonlinear resonator can be realized by connecting the quarter wavelength impedance transformation lines with the same center frequency according to the specific characteristic impedance; 2) the preparation process is simple, compared with the gradually changing structure impedance transformation line, the design and preparation process are relatively simple, the process precision and links required for sample preparation are reduced, and the yield and stability of sample preparation are improved; 3) the sample is prepared on a lanthanum aluminate substrate instead of a conventional high-resistance silicon substrate or a sapphire substrate, which meets the precision required for sample preparation, and makes the preparation process simpler and more stable; 4) based on the design scheme of the multi-section quarter wavelength impedance transformation line, excellent gain bandwidth characteristics can be obtained at multiple center frequencies, and excellent gain frequency coverage frequency bands are exhibited; 5) based on the design scheme of the multi-section quarter wavelength impedance transformation line, high gain and wide bandwidth characteristics are exhibited at the design center frequency, and a gain of more than 15dB and a bandwidth of about 580MHz are obtained. BRIEF DESCRIPTION OF DRAWINGS

[0021] Figure 1 is the circuit design diagram of the Josephson parametric amplifier based on the multi-section quarter wavelength impedance transformation line of the application.

[0022] Figure 2 is the circuit design diagram of the multi-section quarter wavelength impedance transformation line of the application.

[0023] Figure 3This is a circuit design suggestion for the superconducting Josephson junction nonlinear resonator of the present invention.

[0024] Figure 4 This is a measurement circuit diagram of the parametric amplifier of the present invention.

[0025] Figure 5 It is the flux modulation phase spectrum of the center frequency of the nonlinear resonator of the parametric amplifier of the present invention.

[0026] Figure 6 1 is a gain-frequency curve diagram of the parametric amplifier of the present invention at different center frequencies.

[0027] Figure 7 It is a gain frequency curve diagram of the parametric amplifier of the present invention at a center frequency of about 5.45 GHz. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical solutions and advantages of this application more clear, the following further describes this application in detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain this application and are not intended to limit this application.

[0029] like Figure 1 As shown, a Josephson parametric amplifier based on a multi-section quarter-wavelength impedance transformation line includes an amplifier input and output port 101, a multi-section quarter-wavelength impedance transformation line 102, a superconducting Josephson junction nonlinear resonator 103 and its corresponding magnetic flux bias line 104; one end 201 of the multi-section quarter-wavelength impedance transformation line is connected to the input and output port 101, and the other end 206 is connected to the superconducting Josephson junction nonlinear resonator 103; the other end of the superconducting Josephson junction nonlinear resonator 103 is connected to the magnetic flux bias line 104.

[0030] A microwave signal to be amplified is input into the input / output port 101, transmitted through the multi-section quarter-wavelength impedance transformation line 102, and then input into the superconducting Josephson junction nonlinear resonator 103. Simultaneously, a direct current and a pump signal are input into the magnetic flux bias line 104. By changing the direct current, the magnetic flux passing through the superconducting quantum interference device 303 is adjusted, and its equivalent inductance is changed, thereby adjusting the operating frequency of the superconducting Josephson junction nonlinear resonator 103. The nonlinear inductance of the superconducting Josephson nonlinear resonator is used to achieve mixing between the input pump signal and the signal to be amplified, converting the energy of the pump signal into the energy required for amplification of the input signal. The amplified signal is reflected along the input transmission line and output through the input / output port 101. A microwave circulator is connected to the input / output port 101 to achieve separation of the input and output signals.

[0031] like Figure 2As shown, the multi-section quarter wavelength impedance transformation line 102 is composed of a first section quarter wavelength impedance transformation line 202, a second section quarter wavelength impedance transformation line 203, a third section quarter wavelength impedance transformation line 204 and a fourth section quarter wavelength impedance transformation line 205. Each of the above-mentioned section quarter wavelength impedance transformation lines is designed in the form of a planar coplanar waveguide transmission line, and the main feature is that the characteristic impedance of the transmission line can be adjusted by changing the ratio of the center conductor width to the gap width, and the higher the ratio of the center conductor width to the gap width, the lower the characteristic impedance of the planar coplanar waveguide transmission line; in addition, the characteristic impedance of the transmission line is also determined by the chip substrate used by the parametric amplifier, and under the condition that the ratio of the center conductor width to the gap width is constant, the greater the relative dielectric constant of the chip substrate, the lower the characteristic impedance value of the transmission line. The specific design parameter determination process is as follows: let the characteristic impedances of each section of the multi-section quarter wavelength impedance transformation line 102 be Z1, Z2, Z3 and Z4 respectively, and the impedances of the input / output port and the superconducting Josephson junction nonlinear resonator be Z0=50Ω and Z L =15Ω respectively, where the characteristic impedance of the input / output port can be equivalent to the impedance value of the external environment. The characteristic impedance of each section of the impedance transmission line can be determined according to N=4, where N is the number of sections of the multi-section quarter wavelength impedance transformation line.

[0032] As shown in Figure 3 , the superconducting Josephson junction nonlinear resonator is composed of a parallel plate capacitor 302 and a nonlinear inductor in parallel, where the nonlinear inductor is an equivalent inductor composed of a direct current superconducting quantum interference device 303 composed of two superconducting Josephson junctions in parallel. The input end 301 of the parallel plate capacitor is connected to the fourth section quarter wavelength impedance transformation line 205, and the ground end 304 of the direct current superconducting quantum interference device 303 is connected to the magnetic flux bias line 104. By changing the current input to the magnetic flux bias line 104, the magnetic flux passing through the superconducting quantum interference device 303 is adjusted, the equivalent inductance is changed, and the working frequency of the superconducting Josephson junction nonlinear resonator 103 is adjusted. In addition, the magnetic flux bias line 104 also has the pump signal energy required by the amplified microwave signal of the parametric amplifier, and inputs the pump signal to the direct current superconducting quantum interference device 303, so as to realize the mixing between the input pump signal and the signal to be amplified.

[0033] In this embodiment, the input / output port 101, the multi-section quarter wavelength impedance transformation line 102 and the magnetic flux bias line 104 all use niobium film with a thickness of 90nm to 120nm. The upper plate of the parallel plate capacitor 302 of the superconducting Josephson junction nonlinear resonator 103 is aluminum with a thickness of 200nm, the dielectric layer is silicon nitride with a thickness of 200nm, and the lower plate is niobium; the direct current superconducting quantum interference device 303 uses an aluminum-aluminum oxide-aluminum three-layer structure Josephson junction.

[0034] Further, the input and output ports 101, the multi-section quarter-wave impedance transformation line 102, the lower plate of the parallel-plate capacitor 302, and the magnetic flux bias line 104 are exposed to laser direct writing and are prepared by reactive ion etching in the process of preparing the above-mentioned parametric amplifier. The dielectric layer of the parallel-plate capacitor 302 is grown by plasma-enhanced chemical vapor deposition, and is exposed to laser direct writing and prepared by reactive ion etching. The upper plate of the parallel-plate capacitor 302 is prepared by laser direct writing, electron beam evaporation, and peeling. The direct current superconducting quantum interference device 303 is prepared by laser direct writing or electron beam lithography and double-angle electron beam evaporation.

[0035] Further, the precision limit of the laser direct writing lithography used in this scheme is about 1 μm. In order to meet the preparation precision requirements of the parametric amplifier and improve the yield of the parametric amplifier, the gap width of the planar coplanar waveguide transmission line of the multi-section quarter-wave impedance transformation line 102 needs to be greater than or equal to 3 μm.

[0036] Further, the substrate of the parametric amplifier is usually a high-resistance silicon or sapphire substrate with a thickness of 430 μm to 500 μm. The lanthanum aluminate substrate with a thickness of 500 μm and a higher relative dielectric constant than the high-resistance silicon or sapphire substrate is optimized. The characteristic impedance of the fourth-section quarter-wave impedance transformation line needs to be 18 Ω. In order to increase the ratio of the center conductor width to the gap width of the planar coplanar waveguide transmission line, the width of the transmission line gap needs to be reduced while keeping the center conductor width unchanged. In order to meet the process precision of 1 μm of the laser direct writing lithography, the transmission line gap width needs to be kept greater than or equal to 3 μm. The lanthanum aluminate substrate with a higher relative dielectric constant than the high-resistance silicon or sapphire substrate can further reduce the characteristic impedance of the transmission line while keeping the center conductor width and the gap width unchanged, so that the characteristic impedance of the fourth-section quarter-wave impedance transformation line is 18 Ω, and the transmission line gap width is kept greater than or equal to 3 μm. The precision limit of the laser direct writing lithography is met, and the process preparation precision of the parametric amplifier is met, thereby improving the yield of the parametric amplifier chip.

[0037] Further, the center working frequencies of the first-section quarter-wave impedance transformation line 202, the second-section quarter-wave impedance transformation line 203, the third-section quarter-wave impedance transformation line 204, and the fourth-section quarter-wave impedance transformation line 205 are the same, so that the impedance matching from 50 Ω to 15 Ω of the nonlinear resonator at the required center frequency is realized.

[0038] Embodiment

[0039] In order to verify the effectiveness of the scheme of the present invention, the following experimental design was carried out.

[0040] In this embodiment, the parametric amplifier chip substrate is made of lanthanum aluminate, which has a relative dielectric constant of 23.4. The metal materials used for the impedance transformation lines and the superconducting Josephson junction nonlinear resonator are niobium or aluminum, with a thickness of 90 nm to 120 nm. Each section of the designed multi-section quarter-wavelength impedance transformation line 102 is 2944 μm long, and the characteristic impedances of each section are, from left to right, 46 Ω, 34 Ω, 26 Ω, and 18 Ω, respectively.

[0041] The parallel plate capacitance of the superconducting Josephson junction nonlinear resonator 103 is about 4.5 pF; the critical current of a single Josephson junction of its DC superconducting quantum interference device 303 is 1.8 μA, its inherent inductance is about 3.5 pH, and the maximum resonant frequency of the superconducting Josephson nonlinear resonator 103 is about 7.7 GHz.

[0042] like Figure 4 As shown in the figure, the actual measurement circuit diagram required for measuring the actual device sample in this example under the 30mK low-temperature test environment provided by the dilution refrigerator. The microwave signal to be amplified, generated by the vector network analyzer, passes from the output port through the measurement circuit from room temperature to 30mK, enters through port 1 of the microwave circulator, outputs from port 2, and is connected to the input and output ports of the parametric amplifier. The signal is amplified by the amplifier and reflected back to the input and output ports. The reflected signal enters along port 2 of the microwave circulator and outputs from port 3. It is input into the vector network analyzer through the measurement circuit from 30mK to room temperature, and the S21 parameter of the vector network analyzer is read to obtain the S11 parameter of the parametric amplifier. The entire measurement system circuit design is reasonable and fully functional. Based on the comprehensive measurement plan prepared based on this system, it is possible to well characterize the various performance characteristics of the prepared parametric amplifier, which further proves the excellence of this measurement system.

[0043] like Figure 5 Figure 2 shows the phase spectrum of the nonlinear resonator center frequency as a function of bias current, measured for an actual device sample in this embodiment under the 30mK low-temperature test environment provided by a dilution refrigerator. By varying the DC voltage applied to the flux bias line 104, the center frequency of the superconducting Josephson junction nonlinear resonator 103 can be varied. Using the formula for fitting, the flux bias fitting curve (red dashed line) is obtained. The center frequency can be modulated from 7.7GHz to 4GHz, with an adjustable range exceeding 3GHz. This demonstrates that the superconducting Josephson nonlinear resonator 103 in this parametric amplifier is functioning properly and exhibits excellent center frequency tunability.

[0044] like Figure 6As shown, the gain bandwidth of the parametric amplifier at different center frequencies is measured in the actual device sample in the embodiment under the 30mK low-temperature test environment. By changing the direct current voltage input to the magnetic flux bias line 104 and selecting appropriate pump signal frequency and power, the amplification of the parametric amplifier to the input microwave signal can be observed. By applying and turning off the pump signal, the S 21 The gain frequency curve of the parametric amplifier at different center frequencies can be obtained by comparing the front and back changes of the parameters and recording them. The parametric amplifier can achieve the gain curves at the center frequencies of 4.95GHz, 5.05GHz, 5.22GHz, 5.45GHz, 6.04GHz, and 7.0GHz by selecting appropriate direct current signals and corresponding pump signals. The gain curve range covers the frequency range of 5GHz to 7GHz, and the bandwidth corresponding to the gain of more than 15dB is about 80MHz to 580MHz, which proves that the parametric amplifier has excellent gain frequency coverage frequency band.

[0045] As shown, the gain frequency curve of the parametric amplifier at different center frequencies is measured in the actual device sample in the embodiment under the 30mK low-temperature test environment. By changing the direct current voltage input to the magnetic flux bias line 104 and selecting appropriate pump signal frequency and power, the amplification of the parametric amplifier to the input microwave signal can be observed. By applying and turning off the pump signal, the S Figure 7 As shown, the gain frequency curve of the parametric amplifier at different center frequencies is measured in the actual device sample in the embodiment under the 30mK low-temperature test environment. By changing the direct current voltage input to the magnetic flux bias line 104 and selecting appropriate pump signal frequency and power, the amplification of the parametric amplifier to the input microwave signal can be observed. By applying and turning off the pump signal, the S

[0046] The technical features of the above embodiments can be combined in any way. In order to make the description concise, not all possible combinations of the technical features in the above embodiments are described, but as long as the combinations of the technical features do not contradict, they should be considered as within the scope of the present application.

[0047] The above-described embodiments only express several implementation manners of the present application, and the description is relatively specific and detailed, but it should not be understood as a limitation on the scope of the present application. It should be noted that for ordinary skilled persons in the art, some modifications and improvements can be made without departing from the concept of the present application, and these are within the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the appended claims.

Claims

1. A Josephson parametric amplifier based on a multi-section quarter-wavelength impedance transformation line, characterized in that: The invention comprises an input / output port (101), a multi-section quarter-wavelength impedance transformation line (102), a superconducting Josephson junction nonlinear resonator (103) and a magnetic flux bias line (104); one end (201) of the multi-section quarter-wavelength impedance transformation line is connected to the input / output port (101), and the other end (206) is connected to the superconducting Josephson junction nonlinear resonator (103); the other end of the superconducting Josephson junction nonlinear resonator (103) is connected to the magnetic flux bias line (104), wherein: The multi-section quarter-wavelength impedance transformation line (102) comprises a first section quarter-wavelength impedance transformation line (202), a second section quarter-wavelength impedance transformation line (203), a third section quarter-wavelength impedance transformation line (204) and a fourth section quarter-wavelength impedance transformation line (205). The four sections quarter-wavelength impedance transformation lines are all in the form of a planar coplanar waveguide transmission line. The characteristic impedances of the quarter-wavelength impedance transformation lines are Z1, Z2, Z3 and Z4 respectively. The impedances of the input and output ports and the superconducting Josephson junction nonlinear resonator are Z0, Z1 and Z2 respectively. L , then the characteristic impedance of each quarter-wavelength impedance transformation line is based on The impedance transformation line is determined by N=4, where N is the number of sections of the multi-section quarter-wavelength impedance transformation line.

2. The Josephson parametric amplifier based on a multi-section quarter-wavelength impedance transformation line according to claim 1, characterized in that: The characteristic impedance of the quarter-wavelength impedance transformation line is adjusted by changing the ratio of the center conductor width to the slot width of the transmission line. The higher the ratio of the center conductor width to the slot width, the lower the characteristic impedance of the planar coplanar waveguide transmission line. In addition, the characteristic impedance is also related to the chip substrate material. Under the condition that the ratio of the center conductor width to the slot width of the transmission line is constant, the larger the relative dielectric constant of the chip substrate is, the lower the characteristic impedance value of the transmission line is.

3. The Josephson parametric amplifier based on a multi-section quarter-wavelength impedance transformation line according to claim 1, characterized in that: The lanthanum aluminate substrate with a thickness of 500 μm was used for preparation.

4. The Josephson parametric amplifier based on a multi-section quarter-wavelength impedance transformation line according to claim 1, characterized in that: The superconducting Josephson junction nonlinear resonator (103) is formed by connecting a parallel plate capacitor (302) and a nonlinear inductor in parallel, wherein: The nonlinear inductor is a DC superconducting quantum interference device (303) composed of two superconducting Josephson junctions connected in parallel, the input end (301) of the parallel plate capacitor is connected to the fourth quarter-wavelength impedance transformation line (205), and the ground end (304) of the DC superconducting quantum interference device (303) is connected to the magnetic flux bias line (104).

5. The Josephson parametric amplifier based on a multi-section quarter-wavelength impedance transformation line according to claim 4, characterized in that: The working process is: The microwave signal to be amplified is inputted into the input / output port (101), and after being transmitted through the multi-section quarter-wavelength impedance transformation line (102), it is inputted into the superconducting Josephson junction nonlinear resonator (103); A magnetic flux bias line (104) inputs a direct current and a pump signal. By changing the direct current, the magnetic flux passing through the superconducting quantum interference device (303) is adjusted, and its equivalent inductance is changed, thereby adjusting the operating frequency of the superconducting Josephson junction nonlinear resonator (103). The nonlinear inductance of the superconducting Josephson nonlinear resonator is used to achieve mixing between the input pump signal and the signal to be amplified, and the energy of the pump signal is converted into energy required for amplifying the input signal. The amplified signal is reflected along the input transmission line and output through the input / output port (101). A microwave circulator is connected to the input / output port (101) to achieve separation of the input and output signals.

6. The Josephson parametric amplifier based on a multi-section quarter-wavelength impedance transformation line according to claim 1, characterized in that: The input and output ports (101), the multi-section quarter-wavelength impedance transformation line (102) and the magnetic flux bias line (104) are all made of niobium film with a thickness of 90nm to 120nm.

7. The Josephson parametric amplifier based on a multi-section quarter-wavelength impedance transformation line according to claim 4, characterized in that: The upper plate of the parallel plate capacitor (302) of the superconducting Josephson junction nonlinear resonator (103) is made of aluminum, the dielectric layer is made of silicon nitride with a thickness of 200 nm, and the lower plate is made of niobium.

8. The Josephson parametric amplifier based on a multi-section quarter-wavelength impedance transformation line according to claim 3, characterized in that: The DC superconducting quantum interference device (303) adopts a three-layer structure Josephson junction of aluminum-aluminum oxide-aluminum.

9. The Josephson parametric amplifier based on a multi-section quarter-wavelength impedance transformation line according to claim 1, characterized in that: The multi-section quarter-wavelength impedance transformation line (102) adopts laser direct writing lithography, the precision limit of the laser direct writing lithography is about 1 μm, and the gap width of the planar coplanar waveguide transmission line of the multi-section quarter-wavelength impedance transformation line reaches more than 3 μm.

10. The Josephson parametric amplifier based on a multi-section quarter-wavelength impedance transformation line according to claim 1, characterized in that: The center operating frequencies of the first quarter-wavelength impedance transformation line (202), the second quarter-wavelength impedance transformation line (203), the third quarter-wavelength impedance transformation line (204) and the fourth quarter-wavelength impedance transformation line (205) are the same.

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