A traveling wave microwave optical quantum detection method and system and a superconducting quantum circuit

Abstract

The application discloses a kind of travelling wave microwave light quantum detection method, system and a superconducting quantum circuit, wherein the travelling wave microwave light quantum detection method includes: establishing three-level dimer coupling wQED system model;Based on system model, obtain the equation set containing system model input-output relationship and photon detection efficiency expression;Based on equation set and photon detection efficiency expression, obtain key parameter group;According to key parameter group, adjust the structure and coupling relationship of system model, realize the detection of travelling wave microwave light quantum based on adjusted system model.In the present application, this kind of brand-new three-level dimer coupling wQED system model is proposed, under the condition of reasonable setting key parameter group, adjust its structure and coupling relationship, and then realize high-efficiency detection with far less than the number of atoms of traditional scheme in principle to realize large bandwidth, greatly save physical resources, simplify the complexity of system.

Description

Technical Field

[0001] This invention relates to the field of photon detection technology, and in particular to a traveling wave microwave optical quantum detection method, system, and a superconducting quantum circuit. Background Technology

[0002] Single-photon detection technology plays a crucial role in fields such as quantum computing, quantum sensing, and space exploration, while also promoting the development of superconducting technology, photoelectric detection, and photoelectric conversion technologies to a certain extent. In the optical band, commonly used single-photon detection devices include photomultiplier tubes, avalanche photodiodes, and superconducting nanowire single-photon detectors, and these applications are relatively mature. However, in the microwave band, the detection of traveling-wave microwave photons still faces significant challenges. This technology has extremely high application value in microwave quantum optics, quantum radar, and quantum information processing.

[0003] Traditional microwave detection technologies mainly include those based on classical electromagnetic induction, thermoelectric effect, and photoelectric effect. However, these technologies struggle to detect quantum-level traveling wave microwave photons. Currently, a feasible detection scheme utilizes atoms as detectors, achieving detection through resonant absorption. However, this scheme has significant drawbacks: the interaction between the traveling wave microwave photon and the atomic detector is extremely weak, and impedance mismatch limits the theoretical detection efficiency of a single atomic detector for a single traveling wave microwave photon to a maximum of 50%. Overcoming this limit requires a significant increase in the number of atomic detectors, leading to resource waste and increased technological complexity. Furthermore, this scheme, which relies on a large increase in the number of atomic detectors, only detects a very narrow frequency range near the resonant frequency, resulting in an extremely narrow effective working bandwidth.

[0004] Therefore, how to provide an efficient detection method for traveling wave microwave photons is a technical problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0005] To address the aforementioned technical problems, this invention proposes a traveling wave microwave optical quantum detection method, which can significantly improve the detection efficiency of traveling wave microwaves.

[0006] Specifically, in a first aspect, the present invention provides a traveling-wave microwave optical quantum detection method, the method comprising:

[0007] S1 establishes a wQED system model with three-level dimer coupling;

[0008] S2, based on the system model, obtains a set of equations containing the input-output relationship of the system model and an expression for photon detection efficiency;

[0009] S3 obtains the key parameter set based on the aforementioned set of equations and the photon detection efficiency expression;

[0010] S4 adjusts the structure and coupling relationship of the system model according to the key parameter set, and realizes the detection of traveling wave microwave photons based on the adjusted system model.

[0011] By proposing a novel three-level dimer coupled wQED system model, and by rationally setting key parameter groups and controlling the structure and coupling relationship, it can achieve high-bandwidth and high-efficiency detection with a number of atoms far less than traditional schemes, thereby significantly saving physical resources and simplifying system complexity.

[0012] In some embodiments of the present invention, the method further includes that the three-level dimer coupled wQED system model consists of a one-dimensional waveguide and a periodic three-level dimer atom array coupled thereto; the periodic three-level dimer atom array consists of a plurality of periodically arranged dimer cells, each dimer cell containing two identical three-level atoms;

[0013] The key parameter set includes: the spacing between each three-level atom in the dimer cell, the spacing between each dimer cell, the coupling strength between each three-level atom in the dimer cell, and the coupling strength between each three-level atom and the one-dimensional waveguide.

[0014] By precisely controlling the coupling strength and atomic distance, the energy coupling efficiency and artificial atom mutual coupling characteristics of the wQED system are optimized, achieving optimal parameter matching, improving the absorption and conversion efficiency of traveling wave microwave photons, and enhancing detection sensitivity and stability; the composition of key parameter groups is clarified, providing optimization directions, simplifying debugging, and reducing difficulty.

[0015] In some embodiments of the present invention, the method further includes step S2, which specifically includes:

[0016] S21 calculates the Hamiltonian and eigenfunctions of the system model based on the system model;

[0017] S22 solves the time-independent Schrödinger equation based on the Hamiltonian and eigenfunctions, thereby obtaining a set of equations containing the input-output relationship of the system model;

[0018] S23 obtains the photon detection efficiency expression based on the system model.

[0019] By deriving the system's Hamiltonian, eigenfunctions, and input-output equations, and combining this with photon detection efficiency, the signal transmission and photon detection mechanisms of the wQED system are precisely characterized from the principles of quantum mechanics. A theoretical correlation is established between quantum properties, transmission properties, and detection performance; the intrinsic connection between structure and transmission / detection is quantified; and the influence of structural elements on detection performance is clarified. This provides precise theoretical support for parameter analysis and optimization, avoids research blind spots, and ensures the scientific rigor and relevance of system design optimization.

[0020] In some embodiments of the present invention, the method further includes step S3, which specifically includes:

[0021] The optimal efficiency condition of the system model is determined based on the photon detection efficiency expression, wherein the optimal efficiency condition is that both transmittance and reflectance are 0.

[0022] The equations are analyzed analytically to determine the key parameter set, so as to ensure that the system model forms a Dirac point in its band structure under the parameter conditions of the key parameter set, thereby making the transmittance and reflectance of the system model meet the optimal efficiency condition.

[0023] By analyzing relevant equations and detection efficiency, a set of key parameters is obtained, and structural parameters suitable for efficient detection are selected. This set of parameters enables the system to form a Dirac-type point, which suppresses its transmittance and reflectance to zero over a wide frequency range, achieving efficient absorption detection of microwave photons and improving broadband detection efficiency and stability. Based on theory and performance indicators, parameters are determined to ensure optimal performance matching and provide core parameter support for broadband efficient detection.

[0024] In some embodiments of the present invention, the method further includes step S4, which specifically includes: adjusting the structure and coupling relationship of the system model according to the key parameter set; calculating the relationship between the detection efficiency and detuning based on the key parameter set and the adjusted system model, thereby obtaining the optimal detection frequency range, and detecting traveling wave microwave photons within the optimal detection frequency range.

[0025] Based on numerical calculations of key parameter sets, the correlation between detection efficiency and detuning is determined, clarifying the optimal detection frequency range of the system and providing a reliable frequency adaptation basis for precise microwave photon detection. Only photons in this frequency band are detected, ensuring the detection efficiency and stability of the target frequency band and achieving perfect detection results stably.

[0026] In a second aspect, the present invention provides a traveling wave microwave optical quantum detection system, the system comprising: a traveling wave microwave optical quantum detection module, the detection module comprising a one-dimensional waveguide and a periodic three-level dimer atom array coupled thereto;

[0027] The one-dimensional waveguide is used to carry and conduct the traveling wave microwave photons;

[0028] The atomic array is used to exchange and absorb energy with the traveling wave microwave photon, thereby obtaining and outputting the voltage response signal corresponding to the traveling wave microwave photon.

[0029] The detection system in this invention is a traveling wave microwave photon detection system with a three-level dimer coupled wQED structure. It has the advantages of controllable coupling, optimizable energy band, stable quantum state, and flexible structure. The optimal system can be formed by adjusting key parameters. Moreover, the structure is simple and highly scalable, reducing engineering complexity and providing core structural support for efficient and accurate detection.

[0030] In some embodiments of the present invention, the system further includes: a microwave single-photon source and a signal readout and display module; the microwave single-photon source, the traveling wave microwave photon detection module, and the signal readout and display module are connected in sequence.

[0031] The microwave single-photon source is used to prepare and emit the traveling wave microwave photons to the traveling wave microwave photon detection module;

[0032] The signal readout and display module is used to receive the voltage response signal output by the traveling wave microwave photonic quantum detection module, and to process and display the voltage response signal.

[0033] By setting up a microwave single-photon source, a traveling-wave microwave photon detection module, and a signal processing and readout module, the architecture is simple and highly efficient. It provides integrated hardware support for high-fidelity microwave photon detection by stabilizing the front-end signal, achieving high-efficiency broadband detection at the core, and accurately processing and reading out at the back-end.

[0034] In some embodiments of the present invention, the signal readout and display module specifically includes a processing module and a display module, wherein the processing module includes a signal preprocessing module, a signal conversion module, and an analysis module;

[0035] The signal preprocessing module is used to amplify the voltage response signal and to filter out environmental interference signals and noise signals in the voltage response signal, so as to finally obtain an effective voltage response signal.

[0036] The signal conversion module is used to convert the effective voltage response signal into a standard signal that can be recognized and processed by the analysis module.

[0037] The analysis module is used to parse and process the standard signal to extract feature information from the signal;

[0038] The display module is used to receive the feature information and display it in a visual form.

[0039] By setting up a signal readout and display module, the weak voltage response signal of the entire processing coupled circuit is amplified, denoised, converted, and analyzed. Interference is filtered out, effective signals are purified, errors are reduced, and detection reliability is improved.

[0040] In a third aspect, the present invention provides a superconducting quantum circuit, the superconducting quantum circuit comprising: a coplanar transmission line and a plurality of coupling circuit groups; each coupling circuit group includes two coupling circuits arranged in parallel, and a second capacitor is connected in series between the two coupling circuits; a first capacitor is connected in series between the coplanar transmission line and each of the coupling circuits respectively.

[0041] The coplanar transmission line is used to transmit traveling wave microwave photons;

[0042] The coupling circuit is used to receive the traveling wave microwave photon and exchange and absorb energy with it, thereby outputting a voltage response signal corresponding to the traveling wave microwave photon.

[0043] The first capacitor is used to adjust the coupling strength between the coupling circuit and the coplanar transmission line;

[0044] The second capacitor is used to adjust the coupling strength between the two coupling circuits.

[0045] This superconducting quantum circuit is designed with a coplanar transmission line, a coupling circuit, and a first and second capacitor to achieve efficient microwave signal transmission and precise coupling. It has a simple structure, high signal transmission fidelity, and improves working stability and signal interaction accuracy, providing a reliable microwave signal transmission and coupling foundation for subsequent control and readout.

[0046] In some embodiments of the present invention, each coupling circuit includes:

[0047] Josephson knot;

[0048] A DC bias current source electrically connected to the Josephson junction is used to provide bias current to drive the Josephson junction to operate in the target current state;

[0049] And a voltage detection unit connected in parallel with the Josephson junction, used to acquire the voltage signal across the Josephson junction.

[0050] This coupling circuit integrates a Josephson junction, a DC bias current source, and a parallel voltage detection unit, which can accurately drive the Josephson junction to the target current state and simultaneously and efficiently acquire its terminal voltage signal. The three components work together to form a functional closed loop, which is compact and adaptable to the requirements of quantum systems. It provides reliable hardware support for circuit signal coupling and quantum state control, and enhances the overall working stability and detection accuracy.

[0051] This invention provides a traveling-wave microwave optical quantum detection method, system, and a superconducting quantum circuit. The traveling-wave microwave optical quantum detection method includes: establishing a three-level dimer-coupled wQED system model; based on the system model, obtaining a set of equations containing the input-output relationships of the system model and a photon detection efficiency expression; based on the set of equations and the photon detection efficiency expression, obtaining a set of key parameters; adjusting the structure and coupling relationship of the system model according to the key parameter set; and realizing the detection of traveling-wave microwave optical quanta based on the adjusted system model. This invention proposes a novel three-level dimer-coupled wQED system model. By adjusting its structure and coupling relationship under the condition of reasonably setting the key parameter set, it theoretically achieves high-efficiency detection with a large bandwidth using a far fewer number of atoms than traditional schemes, greatly saving physical resources and simplifying the system complexity. Attached Figure Description

[0052] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0053] Figure 1 A flowchart of a traveling wave microwave optical quantum detection method according to the present invention is shown;

[0054] Figure 2 This invention provides a schematic diagram of a wQED system model with three-level dimer coupling.

[0055] Figure 3 This invention illustrates the scattering spectrum and photon detection efficiency of the system under a set of key parameters as a function of... A schematic diagram illustrating the changes;

[0056] Figure 4a A schematic diagram of a traveling wave microwave optical quantum detection system provided by the present invention is shown;

[0057] Figure 4b A schematic diagram of another traveling wave microwave optical quantum detection system provided by the present invention is shown;

[0058] Figure 5a A schematic diagram of a superconducting quantum circuit structure provided by the present invention is shown;

[0059] Figure 5b A schematic diagram of another superconducting quantum circuit structure provided by the present invention is shown. Detailed Implementation

[0060] To enable those skilled in the art to better understand the technical solutions of this invention, the technical solutions of the embodiments of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this invention, and not all of them. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0061] References to "an embodiment," "an exemplary embodiment," etc., in this invention indicate that the described embodiment may include a specific feature, structure, or characteristic, but not every embodiment must include that specific feature, structure, or characteristic. Furthermore, these phrases do not necessarily refer to the same embodiment. Additionally, when a specific feature, structure, or characteristic is described in connection with an embodiment, it is assumed that, whether explicitly described or not, the influence of such feature, structure, or characteristic on other embodiments is within the knowledge of those skilled in the art.

[0062] It should be understood that the terms "length", "width", "upper", "lower", "front", "rear", "first", "second", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the present invention.

[0063] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" or "several" means two or more, unless otherwise explicitly specified.

[0064] It should be noted that the structures, proportions, sizes, etc., shown in the accompanying drawings of this specification are only for the purpose of assisting those skilled in the art in understanding and reading the content disclosed in the specification, and are not intended to limit the conditions under which the present invention can be implemented. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in the proportions, or adjustments to the size, without affecting the effects and objectives that the present invention can produce, should still fall within the scope of the technical content disclosed in the present invention.

[0065] It should be noted that, according to common knowledge, the traveling wave microwave photon in this invention refers to the microwave frequency band, and the photon (i.e., single photon) propagating in the form of a traveling wave is the quantum-level traveling wave microwave photon mentioned above; the three-level atom can be effectively simulated by artificial atoms; the wQED mentioned in this invention is short for waveguide quantum electrodynamics, and the wQED system is a waveguide quantum electrodynamics system, which refers to a system in which one or more (artificial) atoms are coupled with different types of one-dimensional waveguides, so that the atoms interact with a restricted one-dimensional continuous photon mode.

[0066] As mentioned earlier, existing traveling-wave microwave photonic quantum detection technologies suffer from low detection efficiency due to the use of single three-level atoms, and narrow detection bandwidth (frequency range) due to the use of a large number of three-level atoms. This invention proposes a three-level dimeric atom-coupled wQED system (waveguide quantum electrodynamic system) for traveling-wave microwave photonic quantum detection, achieving high-efficiency, wide-bandwidth traveling-wave microwave photon detection with a detection rate of up to 100%. Compared to detection methods using a large number of single atoms, the technology is simpler and the equipment cost is lower.

[0067] Specifically:

[0068] Please see Figure 1 The flowchart of a traveling wave microwave optical quantum detection method according to the present invention is shown. The method specifically includes:

[0069] S1. Establish a wQED system model with three-level dimer coupling; S2. Based on the system model, obtain the system of equations containing the input-output relationship of the system model and the expression for photon detection efficiency; S3. Based on the system of equations and the expression for photon detection efficiency, obtain the key parameter set; S4. Adjust the structure and coupling relationship of the system model according to the key parameter set, and realize the detection of traveling wave microwave photons based on the adjusted system model.

[0070] In this invention, a novel three-level dimer coupled wQED system model is proposed. By adjusting its structure and coupling relationship under the condition of reasonably setting key parameter groups, it can achieve high-efficiency detection with a large bandwidth with far fewer atoms than traditional schemes, which greatly saves physical resources and simplifies the complexity of the system.

[0071] For further details, please refer to Figure 2A schematic diagram of a three-level dimer-coupled wQED system model provided by the present invention is shown. The three-level dimer-coupled wQED system model consists of a one-dimensional waveguide and a periodic three-level dimer atom array coupled thereto; the periodic three-level dimer atom array consists of multiple periodically arranged dimer cells, each dimer cell containing two identical three-level atoms.

[0072] In this invention, a special wQED system model is innovatively designed, which enables efficient detection of traveling wave microwave photons in subsequent steps by precisely designing the parameters of the system model.

[0073] In some embodiments, the key parameter set includes: the spacing between each three-level atom within the dimer cell, the spacing between each dimer cell, the coupling strength between each three-level atom within the dimer cell, and the coupling strength between each three-level atom and the one-dimensional waveguide.

[0074] In this invention, by precisely controlling the coupling strength and atomic distance, the energy coupling efficiency and the mutual coupling characteristics between artificial atoms of the wQED system can be synergistically optimized, achieving optimal matching of system parameters. This significantly improves the system's absorption efficiency and energy conversion efficiency for traveling wave microwave photons, enhancing the system's detection sensitivity and response stability. Simultaneously, by clarifying the core components of the key parameter set, a clear direction for parameter optimization is provided for achieving optimal system detection performance. This simplifies the system debugging process, reduces the difficulty of parameter optimization, and enhances the system's engineering feasibility and mass replication capabilities. It solves the technical problems of low detection efficiency, cumbersome parameter debugging, and difficulty in achieving stable optimal performance in traditional wQED systems.

[0075] Understandably, please continue to refer to Figure 2 Based on the above, the wQED system consists of a one-dimensional waveguide and a periodic three-level dimer atom array coupled to it. The one-dimensional waveguide guides microwave photons to propagate unidirectionally in traveling wave mode. This waveguide can be a coplanar waveguide, a superconducting transmission line, or other waveguide structure supporting microwave transmission. The periodic three-level dimer atom array consists of M periodically arranged dimer cells. Each dimer cell contains two identical " A three-level atom has three energy levels: a stable ground state, and a stable ground state. Metastable excited state and readout state The interatomic distance within the cell is The coupling strength is The spacing between adjacent dimer cells is This forms a spatially periodic structure. The coupling strength between each atom and the waveguide is... This coupling leads to energy exchange between atomic excitations and waveguide photonic modes. Specifically, and These represent the transmission and reflection amplitudes of the system, respectively.

[0076] In some embodiments, step S2 specifically includes: S21 calculating the Hamiltonian and eigenfunctions of the system model based on the system model; S22 solving the time-determined Schrödinger equation based on the Hamiltonian and eigenfunctions to obtain a set of equations containing the input-output relationship of the system model; and S23 obtaining the photon detection efficiency expression based on the system model.

[0077] In this invention, the real-space Hamiltonian and eigenfunctions are first calculated from the system model. Then, these are substituted into the time-independent Schrödinger equation to derive the system's input-output relationship equations. Simultaneously, the photon detection efficiency is obtained by combining the system characteristics. Starting from the core principles of quantum mechanics, the quantum state evolution characteristics, signal transmission laws, and intrinsic mechanisms of photon detection in the wQED system of this invention can be accurately characterized. At the same time, a complete theoretical correlation is constructed between the system's quantum characteristics (Hamiltonian, eigenfunctions), input-output transmission (equations), and detection performance (photon detection efficiency). This clearly quantifies the intrinsic connection between the system structure and transmission and detection characteristics, and intuitively reflects the influence of each structural element of the system on the detection performance. This provides accurate and reliable theoretical support and quantitative analysis basis for the subsequent analytical analysis and optimization of key system parameters, completely avoiding the problem of subsequent research lacking theoretical foundation and proceeding blindly, and ensuring the scientific nature and pertinence of system design and optimization.

[0078] Specifically, step S21 involves calculating the real-space Hamiltonian and eigenfunctions of the system based on the system model:

[0079] In the system model proposed in this invention, only photon detection under near-resonance and non-ultra-strong coupling conditions is considered. Under these conditions, the vortex approximation is highly accurate, so this invention can use the vortex approximation in its calculations. Under the vortex approximation, the real-space Hamiltonian of the system (let the reduced Planck constant) is... The following formula is given:

[0080]

[0081] in, This represents the group velocity of photons in the waveguide. Indicates the first The first cell A rise (fall) operator for 1 atom, Indicates its location. . and These represent the generation and annihilation operators for left (right) row photons, respectively. Represents the atomic ground state With excited state The transition frequency between them. excited state Decay to readout state The rate, used to measure the excited state The occupation of the waveguide. In this Hamiltonian, the first row represents the propagation of traveling wave photons in the waveguide, the second row represents the interaction between the atom and the waveguide, and the third row represents the exchange interaction of the atoms within the cell (the first term) and the spontaneous emission of the atoms (the second term).

[0082] Under near-resonance conditions, the total number of excitations in the system is conserved, so the solution can be found in a single excitation space. In a single excitation space, the scattering eigenstates can be represented as a superposition of single-photon states and atomic excited states in the waveguide; therefore, the eigenfunctions can be specifically expressed as:

[0083]

[0084] in, This represents a vacuum state, meaning the atom is in a vacuum state. Furthermore, there are no photons in the waveguide. This represents the left (right) row photon wavefunction. Indicates the first The first cell The excitation amplitude of each atom. Assume a linear dispersion relation. ( The wave vector representing the photon, A single photon (where is the photon frequency) is incident from the left. The wave functions of the right-row and left-row photons can be expressed as follows:

[0085]

[0086] Regulation . and Representing the local transmission amplitude and reflection amplitude respectively, i.e., the first... The first cell The transmission and reflection amplitudes of individual atoms. For the Heaviside step function:

[0087]

[0088] Equations (3a) and (3b) describe the propagation of photons in the waveguide.

[0089] In some embodiments, step S22 specifically involves solving the time-independent Schrödinger equation based on the Hamiltonian and eigenfunctions described above, and obtaining the input-output relationship of the system.

[0090] Photons from the left An incident object propagates freely within a one-dimensional waveguide; when it reaches the coupling point between the atom and the waveguide... When the incident photon interacts with the atoms within the coupled cell, it may be transmitted, reflected, or absorbed.

[0091] Substituting the Hamiltonian (1) and eigenfunction (2) into the time-independent Schrödinger equation Solving this time-state Schrödinger equation and performing some algebraic simplifications, we can obtain the equation satisfied by the system's input-output relationship as follows:

[0092]

[0093] in, This represents the attenuation efficiency from the atom to the waveguide. The inter-cell linkages satisfy: , The boundary conditions are: , This indicates that the photon is incident from the left. The system's transmission amplitude. (i.e., the transmission amplitude of the last atom in the last cell), reflection amplitude (i.e., the reflected amplitude of the first atom in the first cell). This represents the normalized atomic excitation amplitude, satisfying... . This indicates a mistuning between the photon frequency and the atomic transition frequency. This indicates that the photon has traveled to the th The first cell The cumulative phase of each atom. From the probabilistic interpretation of the wave function, the total transmittance of the system can be expressed as: The reflectivity is This set of equations clearly describes how incident photons are scattered and absorbed by the atomic array.

[0094] In some embodiments, step S23 specifically involves obtaining a photon detection efficiency expression.

[0095] System single-photon detection efficiency Defined as being absorbed and causing an atom to transition to a readout state. The photon probability. Due to the excited state. The number of occupancy will increase at a rate decay to By measuring The absorption event can be confirmed by observing the state. Therefore, the expression for photon detection efficiency is:

[0096]

[0097] Furthermore, step S3 specifically includes: determining the optimal efficiency condition of the system model based on the photon detection efficiency expression, where the optimal efficiency condition is that both transmittance and reflectance are 0; performing analytical analysis on the equation set to determine the key parameter set, ensuring that the system model forms Dirac-type points in its band structure under the parameter conditions of the key parameter set, thereby making the transmittance and reflectance of the system model satisfy the optimal efficiency condition. That is, determining the key parameter set of the system to achieve 100% broadband detection efficiency.

[0098] Specifically:

[0099] As can be seen from formula (5), the single-photon detection efficiency is negatively correlated with transmittance and reflectance. and The smaller, The larger the value, the higher the detection efficiency. The necessary and sufficient condition is: This means that the incident photon was neither transmitted nor reflected, but was completely absorbed by the dimer atomic array, corresponding to the perfect impedance matching condition. That is, the transmittance and reflectance of this system model are respectively... That is, the optimal efficiency condition of the system is determined by the photon detection efficiency expression, which is that the transmittance is 0.

[0100] Further analysis of the aforementioned input-output equations reveals that, when the system structural parameters meet specific conditions, it can be achieved within a continuous frequency range. Inspired by relevant research, this invention has identified a set of key parameters: (in Under these parameter conditions, a Dirac-type point will appear in the system's band structure, causing the transmittance and reflectance to be suppressed to zero simultaneously over a wide frequency range near this point. At this time, the transmittance and reflectance of the system model satisfy the aforementioned optimal efficiency condition, i.e., all are 0. Therefore, this set of parameters can be determined as the required key parameter set, thus obtaining the specific key parameter set.

[0101] Understandably, this invention obtains a set of key system parameters by analytically analyzing the input-output relationship equations and photon detection efficiency. Based on the quantitative correlation between system transmission characteristics and detection performance, it can accurately select structural parameters that enable the system to meet specific conditions for efficient detection. The key parameter set determined in this way enables the system's band structure to form a Dirac point, thereby allowing the system to simultaneously suppress transmittance and reflectivity to zero within a continuous wide frequency range near the Dirac point, achieving efficient absorption and detection of traveling wave microwave photons, and significantly improving the system's photon detection efficiency and response stability over a wide frequency range. At the same time, relying on both theoretical derivation and performance indicators to obtain the key parameter set avoids the empirical and blind selection of parameters, ensuring a precise match between the obtained parameter set and the system's optimal detection performance, and providing core parameter design support for the system to achieve wideband, high-efficiency traveling wave microwave photon detection.

[0102] In some embodiments, step S4 adjusts the structure and coupling relationship of the system model according to the key parameter set, and realizes the detection of traveling wave microwave photons based on the adjusted system model. Specifically, based on the key parameter set obtained in step S3, the structure and coupling relationship of the aforementioned three-level dimer coupled wQED system model are adjusted, that is, the spacing between each three-level atom in the dimer cell, the spacing between each dimer cell, the coupling strength between each three-level atom in the dimer cell, and the coupling strength between each three-level atom and the one-dimensional waveguide are adjusted. Based on the key parameter set and the adjusted system model, the relationship between the detection efficiency and detuning is calculated, and the optimal detection frequency range is obtained. Traveling wave microwave photons within this optimal detection frequency range are then detected, thereby achieving broadband and efficient detection of traveling wave microwave photons. It should be noted that, theoretically, the detection efficiency of traveling wave microwave photons under this method can reach up to 100%.

[0103] This invention, by numerically calculating the correlation between detection efficiency and detuning based on a set of key parameters, clarifies the specific frequency range within which the system can achieve perfect detection, providing a clear and reliable basis for the accurate detection of traveling wave microwave photons. Furthermore, by detecting only traveling wave microwave photons within this specific frequency range, it effectively avoids detection errors and efficiency losses caused by frequency mismatch, further ensuring the system's detection efficiency and response stability within the target frequency range, and guaranteeing the stable achievement of perfect detection results.

[0104] Based on the above, this invention, by constructing a novel wQED system and combining a complete technical chain of system model calculation, theoretical derivation, parameter optimization, and efficient detection, overcomes the technical difficulties of low detection efficiency, narrow detection frequency range, and system complexity in existing technologies, and achieves wideband and efficient detection of traveling wave microwave photons. Specifically, it has the following beneficial effects:

[0105] 1. By calculating the real-space Hamiltonian and eigenfunctions of the system model, the system's input-output relationship equations are derived by substituting them into the time-independent Schrödinger equation. The photon detection efficiency is obtained by combining the system characteristics, thus constructing a complete theoretical correlation between the system's quantum characteristics, transmission characteristics, and detection performance, providing a precise and reliable theoretical basis for obtaining the key parameter set.

[0106] 2. Based on the above equations and photon detection efficiency, analytical analysis was conducted to screen and determine the core key parameter set: atomic distance, cell distance, atomic-waveguide coupling strength, and interatomic coupling strength. This key parameter set can enable the band structure of the novel wQED system to form a Dirac point, thereby simultaneously suppressing the system's transmittance and reflectance to zero within a continuous wide frequency range near the Dirac point, maximizing the absorption efficiency and energy conversion efficiency of traveling wave microwave photons, and achieving the optimal detection performance of the system.

[0107] 3. Based on the determined key parameter set, the precise correlation between detection efficiency and detuning was obtained through numerical calculation. The frequency range in which the system can achieve perfect detection was then determined. Traveling wave microwave photons within this frequency range were then specifically detected, ensuring the stable realization of perfect detection results and improving the accuracy and stability of the system detection.

[0108] 4. Based on the wQED system constructed from novel artificial atoms and precisely controlled key parameters, the system's detection efficiency, response sensitivity, and response bandwidth for traveling wave micro-quantum light are significantly improved, solving the technical problems of low detection efficiency, narrow response bandwidth, and unstable performance in existing technologies. The clear and concise core system structure, along with the key parameter sets and acquisition methods, greatly simplifies the system parameter optimization and debugging process, reduces the complexity of system design and engineering implementation, and facilitates subsequent promotion and practical application.

[0109] In this invention, to aid understanding, a complete workflow of a simplified traveling-wave microwave optical quantum detection method is provided. It should be noted that this workflow is merely for illustrative purposes and is not intended to limit the actual implementation of this solution.

[0110] In this embodiment, a specific set of parameters is given, and the detection efficiency is calculated in its entirety. With detuning The changes.

[0111] To ensure the high accuracy of the vortex approximation (i.e., the system is in a non-hypercoupled region), preferably, take... To ensure a sufficiently large detection bandwidth while avoiding resource waste and increased technical complexity due to an excessive number of atoms to be detected, preferably, the number of cells is [value missing]. Under the above parameter conditions, the Hamiltonian (1) of the wQED system is rewritten as follows:

[0112]

[0113] The eigenfunction (2) is rewritten as:

[0114]

[0115] The right-row and left-row photon wavefunctions are rewritten as follows:

[0116]

[0117] Preferably, take Parameters are set to ensure the appearance of Dirac-type points in the system's band structure; To ensure and There exists sufficient attenuation efficiency between them to generate a readout voltage signal. Substituting the rewritten Hamiltonian and eigenfunctions into the time-state Schrödinger equation... And by simplifying using the above parameters, we obtain the following system of equations relating the input and output:

[0118]

[0119] The detection efficiency can be obtained by numerically solving this system of equations. With detuning The changes are as follows. Please refer to [link / reference]. Figure 3 This invention illustrates the scattering spectrum and photon detection efficiency of the system under a set of key parameters as a function of... A schematic diagram illustrating the changes. The key parameter group is shown above. It is evident that, in Within a wide frequency window, , This result confirms that, within this frequency range, the detection efficiency is [high / high]. It consistently remains at 100%. This demonstrates that this method has a larger bandwidth (the probe bandwidth can reach...). Its characteristics break through the limitation of existing detection schemes that can only work within an extremely narrow resonance linewidth.

[0120] In some embodiments, based on the above method, the present invention also provides a traveling wave microwave optical quantum detection system. Please refer to [link to relevant documentation]. Figure 4a The diagram shows a schematic of a traveling wave microwave photonic quantum detection system provided by the present invention. The system includes: a traveling wave microwave photonic quantum detection module, the detection module including a one-dimensional waveguide and a periodic three-level dimer atomic array coupled thereto; the one-dimensional waveguide is used to carry and conduct traveling wave microwave photonic quanta; the atomic array is used to exchange energy and absorb energy with the traveling wave microwave photonic quanta, thereby obtaining and outputting the voltage response signal corresponding to the traveling wave microwave photonic quantum.

[0121] In this invention, the detection system is the traveling wave microwave optical quantum detection system with a three-level dimer coupled wQED structure in the aforementioned method. It has the advantages of controllable coupling characteristics, optimizable band structure, stable quantum state, and flexible structure. The optimal system can be formed by adjusting its key parameters. The structure is simple, highly scalable, and reduces engineering complexity, providing core structural support for efficient and accurate detection.

[0122] In some embodiments, please refer to Figure 4b A schematic diagram of another traveling-wave microwave quantum optical detection system provided by the present invention is shown. This traveling-wave microwave quantum optical detection system includes not only the aforementioned traveling-wave microwave quantum optical detection module, but also a microwave single-photon source and a signal readout and display module. The microwave single-photon source, the traveling-wave microwave quantum optical detection module, and the signal readout and display module are connected in sequence. The microwave single-photon source is used to prepare and emit traveling-wave microwave quantum optical signals to the traveling-wave microwave quantum optical detection module. The signal readout and display module is used to receive the voltage response signal output by the traveling-wave microwave quantum optical detection module, process and display the voltage response signal. Furthermore, the signal readout and display module specifically includes a processing module and a display module. The processing module includes a signal preprocessing module, a signal conversion module, and an analysis module. The signal preprocessing module is used to amplify the voltage response signal and filter out environmental interference signals and noise signals in the voltage response signal to finally obtain an effective voltage response signal. The signal conversion module is used to convert the effective voltage response signal into a standard signal that can be recognized and processed by the analysis module. The analysis module is used to analyze and calculate the standard signal to extract feature information from the signal. The display module is used to receive the feature information and display it in a visual form.

[0123] In this invention, the signal readout and display module, through a complete signal amplification, denoising, conversion, and analysis chain, can accurately process the weak voltage response signal output by the coupled circuit, filter out interference, purify the effective signal, reduce detection errors, and improve detection reliability. At the same time, it visualizes the signal characteristics, simplifies the operation process, improves practical ease of use, forms a complete signal closed loop, and adapts to the system's wideband and high-efficiency detection requirements. The modular structure design makes it highly expandable, easy to integrate and maintain, and provides core signal processing and display support for the efficient collaborative operation of the entire detection system.

[0124] Specifically, the core role of the microwave single-photon source in the system is to prepare and emit microwave-band single photons that meet the requirements of quantum detection. As the system's optical quantum signal source, this module is responsible for providing deterministic single-photon events, and its output photon state must possess good single-photonity, spectral purity, and temporal controllability. Upon receiving a synchronization trigger signal, the quantum emission unit of this module performs controlled quantum state evolution, thereby releasing a microwave single photon with energy concentrated in the target frequency band to the connected transmission line channel.

[0125] The traveling-wave microwave quantum optical detection module (wQED system) is the most critical part of the entire system, comprising a transmission line (i.e., a one-dimensional waveguide) and a coupled dimer atom array. Its task is to capture microwave photons transmitted from the transmission line. The frequency is... When a photon reaches the array of dimer atoms, it exchanges energy with the atom and is absorbed. At this point, the atoms return to their ground state due to the absorption of the photon. Excited to excited state and rapidly decay the readout state. The purpose of detecting photons is achieved by reading the voltage response.

[0126] The signal readout and display module is responsible for collecting and displaying the detection results from the detection module. decay to The voltage signal is extremely weak, so it first needs to be amplified using a special amplifier while minimizing the introduction of additional noise. The amplified signal is then transmitted to electronic equipment, where it is converted into a digital signal by a high-speed acquisition card. A computer runs a specific program to analyze these digital signals. When the program identifies a signal pattern that matches the "photon captured" characteristic, it records a detection event and can output and visualize information such as the photon's arrival time.

[0127] In this invention, for the purpose of aiding understanding, a simplified complete workflow of a traveling wave microwave optical quantum detection system is provided. It should be noted that this workflow is only for illustrative purposes and is not intended to limit the actual implementation of this solution.

[0128] S61. Initialization: The atoms in the wQED system are initially prepared in the ground state. .

[0129] S62. Single-photon emission: A microwave single-photon source prepares and emits microwave-frequency single photons that meet the requirements of quantum detection through a one-dimensional waveguide dimer atom array connected to it.

[0130] S63. Single-photon absorption and state transition: When a photon reaches a dimer array of atoms, it exchanges energy with it and is absorbed. The atom absorbs the photon from its ground state. Excited to excited state and rapidly decay the readout state. .

[0131] S64, Signal Readout and Display: by decay to The voltage response signal is sent to the signal reading and display module, amplified, and then transmitted to the electronic device for reading, recording, and display.

[0132] In some embodiments, based on the three-level dimer-coupled wQED system model in the above method and the traveling-wave microwave optical quantum detection module in the above system, this invention proposes a superconducting quantum circuit to implement the above method and / or detection module. Please refer to [link to relevant documentation]. Figure 5a A schematic diagram of a superconducting quantum circuit structure provided by the present invention is shown. The superconducting quantum circuit includes: a coplanar transmission line and multiple coupling circuit groups; each coupling circuit group includes two coupling circuits arranged in parallel, with a second capacitor connected in series between the two coupling circuits; a first capacitor is connected in series between the coplanar transmission line and each coupling circuit; the coplanar transmission line is used to transmit traveling wave microwave photons; the coupling circuits are used to receive traveling wave microwave photons and undergo energy exchange and absorption reactions with them, thereby outputting a voltage response signal corresponding to the traveling wave microwave photons; the first capacitors are used to regulate the coupling strength between the coupling circuits and the coplanar transmission line; and the second capacitors are used to regulate the coupling strength between the two coupling circuits.

[0133] Understandably, this superconducting quantum circuit achieves efficient transmission and precise coupling of microwave signals through the coordinated design of coplanar transmission lines, coupling circuits, and the first and second capacitors. The coplanar transmission lines ensure low-loss and stable transmission of traveling wave micro-photons in the quantum device operating environment. The first and second capacitors can precisely control the coupling strength of microwave signals while effectively isolating DC and AC signals, avoiding interference from DC crosstalk between different circuit modules on signal transmission and coupling effects. The overall circuit design is adapted to the operating requirements of quantum systems, with a simple structure and high signal transmission fidelity, effectively improving the overall circuit's operating stability and signal interaction accuracy, providing a reliable foundation for microwave signal transmission and coupling for subsequent control and readout.

[0134] Please see Figure 5b A schematic diagram of another superconducting quantum circuit structure provided by the present invention is shown. The schematic diagram shows in detail the structure of the above-mentioned coupling circuit. It can be seen that each coupling circuit includes: a Josephson junction; a DC bias current source electrically connected to the Josephson junction for providing bias current to drive the Josephson junction to operate in the target current state; and a voltage detection unit connected in parallel with the Josephson junction for acquiring the voltage signal across the Josephson junction.

[0135] Understandably, in this superconducting quantum circuit, a Josephson junction with current bias acts as the aforementioned "Λ"-type three-level superconducting artificial atom. One coupling circuit is equivalent to one of the aforementioned three-level atoms, and two parallel coupling circuits are equivalent to one of the aforementioned dimer cells. The bias current is... , This represents the nonlinear inductance of a Josephson junction. By adjusting the bias current and nonlinear inductance of the Josephson junction, its energy level structure (including...) can be precisely controlled. and The transition frequency between and and The decay rate between Using coplanar transmission lines as one-dimensional waveguides results in extremely low microwave attenuation, enabling long-distance traveling wave propagation of photons. Intracellular atom-to-atom interactions. and atomic-waveguide coupling Each is capacitively coupled and This is achieved by adjusting these two capacitors, which allows for precise control of the coupling strength. and .

[0136] This invention employs a bus architecture combining superconducting coplanar transmission lines and capacitive coupling, along with independent DC bias and parallel voltage detection units. The overall architecture features low-loss microwave signal transmission, effectively improving quantum information fidelity. It enables precise control of the operating point and high-fidelity manipulation and reading of quantum states for each Josephson junction unit. The circuit adopts a modular design, with each unit independent and compatible with existing quantum device fabrication processes. This effectively reduces the complexity of fabrication, testing, and maintenance, while suppressing external electromagnetic interference and DC bias crosstalk, improving operational stability. It also supports parallel access of multiple coupled circuits and synchronous state reading, combining scalability and efficiency. This provides a hardware foundation for building large-scale quantum computing systems, adaptable to various quantum applications, and possesses the potential for performance iterative upgrades through parameter optimization.

[0137] In this invention, to aid understanding, a simplified complete workflow for detecting traveling wave microwave photons based on this superconducting quantum circuit is provided. It should be noted that this workflow is only for illustrative purposes and is not intended to limit the actual implementation of this solution.

[0138] S91. Initialization: Superconducting artificial atoms based on current-biased Josephson junctions were initially prepared in the ground state. .

[0139] S92. Photon Detection: A microwave single-photon source is linked to a coplanar transmission line. Single photons emitted from the source enter the transmission line and propagate as traveling waves. When the photons reach the atomic array, they interact with the coupled superconducting artificial atoms, causing the atoms to transition from their ground state... Excited to excited state However, this excited state is very unstable and will quickly tunnel to the voltage readout state. This state corresponds to a specific voltage state of the Josephson junction. By reading the corresponding... The voltage response can be used to detect traveling wave microwave photons with high fidelity, thereby confirming a traveling wave microwave photon detection event.

[0140] S93, Signal Acquisition and Readout: The acquired electrical signal is transmitted to the signal readout and display module, which amplifies, reads, and displays it.

[0141] This embodiment demonstrates a feasible process and a specific measurement scheme implementation. It confirms that the method proposed in this invention can be implemented using standard superconducting quantum circuit technology, and its core performance of "high efficiency" and "large bandwidth" can be verified using conventional low-temperature microwave measurement methods. By adjusting design parameters (such as...) , , and (etc.), this solution can be flexibly adapted to detection scenarios with different microwave frequency bands and bandwidth requirements.

[0142] In summary, the beneficial effects of the present invention are as follows:

[0143] 1. A periodic three-level dimer atomic array (wQED) structure for traveling-wave microwave optical quantum detection is proposed. By precisely designing the atomic spacing and coupling parameters, and utilizing the collective quantum interference and cooperative dissipation effect of a finite number of artificial atoms, two major breakthroughs are achieved simultaneously: first, in principle, a detection efficiency of nearly 100% is achieved with a far fewer atom count than traditional schemes; second, the operating bandwidth for efficient detection is extended from a narrow linewidth to a continuous wideband. Specifically:

[0144] Firstly, this invention achieves a high and reliable detection rate while significantly reducing the number of atoms required for efficient detection: Traditional methods often require a large increase in the number of atoms to achieve efficient detection, resulting in high system complexity and low resource utilization. This invention, by employing the structure and coupling relationship of a periodic dimer atomic array, utilizes the collective interference and dissipation effect of a finite number of atoms to achieve 100% detection efficiency in principle, greatly reducing physical resources and simplifying system complexity.

[0145] Secondly, the operating bandwidth is increased by an order of magnitude: By introducing a Dirac-type point into the system's energy band under the specific parameter conditions, this invention transforms the perfect detection range from the resonant frequency to a bandwidth near the resonant frequency that can reach [the desired bandwidth]. The continuous frequency band meets the practical need for efficient detection of traveling wave microwave photons with broadband or inaccurately determined frequencies.

[0146] 2. This invention provides a precisely designed and scalable physical implementation path: It proposes a scheme to realize the wQED system model using superconducting quantum circuits. This scheme utilizes a current-biased Josephson junction to simulate a Λ-type three-level atom and precisely realizes the key parameters in the model through capacitive coupling. This ensures the system possesses high consistency, adjustable parameters, and scalability, providing a clear technical path for practical high-efficiency, high-bandwidth traveling-wave microwave photon detectors.

[0147] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

[0148] The above description is merely a specific implementation of this application and is not intended to limit the scope of protection of this application. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application.

Claims

1. A traveling-wave microwave optical quantum detection method, characterized in that, The method includes: S1 establishes a wQED system model with three-level dimer coupling; S2, based on the system model, obtains a set of equations containing the input-output relationship of the system model and an expression for photon detection efficiency; S3 obtains the key parameter set based on the aforementioned set of equations and the photon detection efficiency expression; S4 adjusts the structure and coupling relationship of the system model according to the key parameter set, and realizes the detection of traveling wave microwave photons based on the adjusted system model; The wQED system model coupled with three-level dimers consists of a one-dimensional waveguide and a periodic array of three-level dimer atoms coupled thereto; the periodic array of three-level dimer atoms consists of multiple periodically arranged dimer cells, each dimer cell containing two identical three-level atoms. The key parameter set includes: the spacing between each three-level atom in the dimer cell, the spacing between each dimer cell, the coupling strength between each three-level atom in the dimer cell, and the coupling strength between each three-level atom and the one-dimensional waveguide.

2. The traveling-wave microwave optical quantum detection method according to claim 1, characterized in that, Step S2 specifically includes: S21 calculates the Hamiltonian and eigenfunctions of the system model based on the system model. S22 solves the time-independent Schrödinger equation based on the Hamiltonian and eigenfunctions, thereby obtaining a set of equations containing the input-output relationship of the system model; S23 obtains the photon detection efficiency expression based on the system model.

3. The traveling-wave microwave optical quantum detection method according to claim 2, characterized in that, Step S3 specifically includes: The optimal efficiency condition of the system model is determined based on the photon detection efficiency expression, wherein the optimal efficiency condition is that both transmittance and reflectance are 0. The equations are analyzed analytically to determine the key parameter set, so as to ensure that the system model forms a Dirac point in its band structure under the parameter conditions of the key parameter set, thereby making the transmittance and reflectance of the system model meet the optimal efficiency condition.

4. The traveling-wave microwave optical quantum detection method according to claim 1, characterized in that, Step S4 specifically includes: adjusting the structure and coupling relationship of the system model according to the key parameter set; calculating the relationship between detection efficiency and detuning based on the key parameter set and the adjusted system model, thereby obtaining the optimal detection frequency range, and detecting traveling wave microwave photons within the optimal detection frequency range.

5. A traveling-wave microwave optical quantum detection system, characterized in that, The system includes: a traveling wave microwave optical quantum detection module, which includes a one-dimensional waveguide and a periodic three-level dimer atom array coupled thereto; The one-dimensional waveguide is used to carry and conduct the traveling wave microwave photons; The atomic array is used to exchange and absorb energy with the traveling wave microwave photon, thereby obtaining and outputting the voltage response signal corresponding to the traveling wave microwave photon; The periodic three-level dimer atom array is composed of multiple periodically arranged dimer cells, each dimer cell containing two identical three-level atoms; The key parameter set related to the traveling wave microwave quantum optical detection module includes: the spacing between each three-level atom in the dimer cell, the spacing between each dimer cell, the coupling strength between each three-level atom in the dimer cell, and the coupling strength between each three-level atom and the one-dimensional waveguide.

6. The traveling-wave microwave optical quantum detection system according to claim 5, characterized in that, The system also includes: a microwave single-photon source and a signal readout and display module; the microwave single-photon source, the traveling-wave microwave quantum detection module, and the signal readout and display module are connected in sequence. The microwave single-photon source is used to prepare and emit the traveling wave microwave photons to the traveling wave microwave photon detection module; The signal readout and display module is used to receive the voltage response signal output by the traveling wave microwave photonic quantum detection module, and to process and display the voltage response signal.

7. The traveling-wave microwave optical quantum detection system according to claim 6, characterized in that, The signal readout and display module specifically includes a processing module and a display module. The processing module includes a signal preprocessing module, a signal conversion module, and an analysis module. The signal preprocessing module is used to amplify the voltage response signal and to filter out environmental interference signals and noise signals in the voltage response signal, so as to finally obtain an effective voltage response signal. The signal conversion module is used to convert the effective voltage response signal into a standard signal that can be recognized and processed by the analysis module. The analysis module is used to parse and process the standard signal to extract feature information from the signal; The display module is used to receive the feature information and display it in a visual form.

8. A superconducting quantum circuit for realizing the wQED system model with three-level dimer coupling as described in claim 1, characterized in that, The superconducting quantum circuit includes: a coplanar transmission line and multiple coupling circuit groups; each coupling circuit group includes two coupling circuits arranged in parallel, and a second capacitor is connected in series between the two coupling circuits; a first capacitor is connected in series between the coplanar transmission line and each of the coupling circuits respectively; The coplanar transmission line is used to transmit traveling wave microwave photons; The coupling circuit is used to receive the traveling wave microwave photon and exchange and absorb energy with it, thereby outputting a voltage response signal corresponding to the traveling wave microwave photon. The first capacitor is used to adjust the coupling strength between the coupling circuit and the coplanar transmission line; The second capacitor is used to adjust the coupling strength between the two coupling circuits.

9. The superconducting quantum circuit according to claim 8, characterized in that, Each coupling circuit includes: Josephson knot; A DC bias current source electrically connected to the Josephson junction is used to provide bias current to drive the Josephson junction to operate in the target current state; And a voltage detection unit connected in parallel with the Josephson junction, used to acquire the voltage signal across the Josephson junction.

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