Quantum chip packaging box, preparation method, quantum processor and quantum computer

Abstract

The invention discloses a quantum chip packaging box and a preparation method thereof, a quantum processor and a quantum computer, the packaging box comprises a packaging cavity used for accommodating a quantum chip, the packaging cavity forms a resonant cavity described by an intrinsic circuit model, the intrinsic circuit model is defined by a first inductor and a first capacitor which are connected in parallel, and the first inductor and the first capacitor are connected in parallel. The packaging structure is characterized in that the packaging structure further comprises a first component equivalent to an inductor and / or a second component equivalent to a capacitor, the first component and the first inductor are arranged in the packaging cavity in parallel, and the second component and the first capacitor are arranged in series. The quantum chip packaging box has the advantages that due to the arrangement of the first component and / or the second component, the lowest-order mode frequency of space resonance corresponding to the packaging box is larger than the frequency of all quantum bits in the quantum chip, and therefore the influence of a resonant cavity formed by the packaging box on the quantum bits is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of quantum computers, and particularly to a quantum chip packaging box and a preparation method thereof, a quantum processor, and a quantum computer. Background Art

[0002] The packaging of quantum chips is one of the important links in quantum computers. In the prior art, quantum chips need to be packaged in a sealed metal cavity structure, and the metal cavity structure is designed with external interfaces for connecting quantum chips and external measurement and control devices. Since superconducting qubits are extremely sensitive to environmental noise, and the sealed metal cavity structure will form a microwave resonator that affects the qubits. Different cavity modes correspond to different sizes of the metal cavity structure, and the cavity mode can generate spatial crosstalk with the qubits, which will have a huge impact on the precise operation of the qubits. Summary of the Invention

[0003] The purpose of the present invention is to reduce the influence of the resonator formed by the packaging box on the qubits. The present application provides a quantum chip packaging box and a preparation method thereof, a quantum processor, and a quantum computer.

[0004] In order to achieve the above purpose, the present invention provides the following technical solutions:

[0005] A quantum chip packaging box includes a packaging cavity for accommodating a quantum chip. The packaging cavity constitutes a resonator described by an eigen-circuit model, and the eigen-circuit model is defined by a first inductor and a first capacitor connected in parallel. It further includes a first component equivalent to an inductor and / or a second component equivalent to a capacitor disposed inside the packaging cavity. The first component is configured to be connected in parallel with the first inductor, and the second component is configured to be connected in series with the first capacitor.

[0006] In one embodiment, the packaging box includes an annular box body part equivalent to a first inductor, and two relatively disposed first box body parts and second box body parts equivalent to a first capacitor.

[0007] In one embodiment, the outer edge of the quantum chip is attached to the inner side wall of the annular box body part.

[0008] In one embodiment, the first component is a metal protrusion located between the first box body part and the second box body part. The metal protrusion passes through the quantum chip and is disposed around the qubits on the quantum chip.

[0009] In one embodiment, the metal protrusion is a metal column, and the metal column is vertically connected to the first box body part and the second box body part.

[0010] In one embodiment, the parameters of the first component include one or more of the number, position, cross-sectional shape, size, material, and distance between adjacent metal protrusions of the metal protrusions. The first components with different parameters are configured to make the corresponding spatial resonance of the encapsulation box have different lowest-order mode frequencies.

[0011] In one embodiment, the second component is a groove formed in the first part and / or the second part of the box body of the encapsulation box.

[0012] In one embodiment, the parameters of the second component include one or more of the relative area parameter, relative distance parameter, and material parameter. The second components with different parameters are configured to make the corresponding spatial resonance of the encapsulation box have different lowest-order mode frequencies.

[0013] In one embodiment, the surfaces of the first component and / or the second component are covered with a protective film.

[0014] The present application also discloses a method for manufacturing an encapsulation box for accommodating a quantum chip, including the following steps:

[0015] According to the qubit size and set conditions, obtain the lowest-order mode frequency corresponding to the eigen circuit model through simulation;

[0016] In the encapsulation box having the eigen circuit model, set the first component and / or the second component, thereby forming a new circuit model describing the encapsulation box and the corresponding first component and / or second component, and the resonance frequency defined by the new circuit model is greater than the frequencies of all qubits in the quantum chip;

[0017] Wherein, the eigen circuit model includes a first capacitor and a first inductor connected in parallel, the new circuit model includes a second inductor provided by the first component and / or a second capacitor provided by the second component, and in the new circuit model, the first capacitor is connected in series with the second capacitor, and the first inductor is connected in parallel with the second inductor.

[0018] In one embodiment, according to the qubit size and set conditions, obtaining the lowest-order mode frequency corresponding to the eigen circuit model through simulation includes the following steps:

[0019] Determine the size of the internal space cavity of the encapsulation box according to the size of the quantum chip, and obtain the value of the lowest-order mode frequency according to the calculation formulas of different sub-mode frequencies of the eigen circuit model. The calculation formulas of different sub-mode frequencies are:

[0020]

[0021] Where n, m, p are integers, representing different cavity modes, l x 、l y 、lz represents the size of the internal space cavity of the encapsulation box in the rectangular coordinate system; the lowest-order mode frequency of the spatial resonance corresponding to the encapsulation box is the lowest frequency of the encapsulation cavity with the set size; ∈ and μ respectively represent the permittivity and permeability of the medium in the encapsulation box, and the lowest-order mode frequency is the minimum value among different-order mode frequencies.

[0022] A quantum processor includes the above-mentioned quantum chip encapsulation box and a quantum chip disposed in the encapsulation cavity of the encapsulation box.

[0023] A quantum computer includes the above-mentioned quantum processor.

[0024] The beneficial effects of the present invention are as follows:

[0025] For a quantum chip encapsulation box disclosed in the present invention, in this application, the overall L in the calculation formula of the resonance frequency is reduced by connecting in parallel a first component equivalent to an inductor in the encapsulation box, and / or the overall capacitance in the calculation formula of the resonance frequency is reduced by connecting in series a second component equivalent to a capacitor, so as to reduce the product value of the capacitance and the inductor in to increase the resonance frequency f. The lowest-order mode frequency of the spatial resonance corresponding to the encapsulation box is the lowest frequency of the encapsulation cavity with the set size, and the lowest-order mode frequency is equal to the resonance frequency. By setting the first component and the second component in this application, the frequency of the lowest-order mode is made greater than the frequencies of all the qubits in the quantum chip, thereby reducing the influence of the resonance cavity formed by the encapsulation box on the qubits.

[0026] A preparation method of an encapsulation box, a quantum processor, and a quantum computer provided by the present invention have the same beneficial effects, which will not be elaborated here. Description of the Drawings

[0027] Figure 1 is a schematic structural diagram of the encapsulation box without the first component and / or the second component in the embodiment of the present invention (the top cover plate is not shown);

[0028] Figure 2 is Figure 1 a side cross-sectional view of

[0029] Figure 3 is an equivalent Figure 1 and Figure 2 encapsulation box as a waveguide rectangular cavity model diagram;

[0030] Figure 4 is an eigen circuit model diagram of the encapsulation box equivalent to the parallel connection of a first inductor and a first capacitor;

[0031] Figure 5 is a schematic structural diagram of a metal column connecting two electrodes disposed in the encapsulation box in an embodiment of the present invention;

[0032] Figure 6 For Figure 5 the equivalent resonance circuit diagram of the encapsulation box in

[0033] Figure 7 This is a schematic structural diagram of a groove formed on the first part of the box body of the encapsulation box in an embodiment of the present invention;

[0034] Figure 8 For Figure 7 the corresponding equivalent resonance circuit diagram of the encapsulation box.

[0035] In the attached drawing reference numerals:

[0036] 1. The first part of the box body; 2. The annular box body part; 3. The second part of the box body; 4. The quantum chip; 5. The metal column; 6. The groove. Specific embodiments

[0037] In order to enable those skilled in the art of the present technology to better understand the technical solutions in this application, the following will clearly and completely describe the technical solutions in the embodiments of this application with reference to the accompanying drawings in the embodiments of this application. Obviously, the described embodiments are only a part of the embodiments of this application, rather than all the embodiments. Based on the embodiments in this application, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of this application. The embodiments described below by referring to the attached drawings are exemplary and are only used to explain this application, and cannot be construed as a limitation of this application.

[0038] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by terms such as "center", "upper", "lower", "left", "right", etc. is based on the orientation or positional relationship shown in the attached drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the present invention.

[0039] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise specifically defined.

[0040] The noun introduction is as follows:

[0041] Read link: It includes the lines for regulating and measuring qubits and the lines for obtaining the qubit feedback signal.

[0042] Purcell effect: In the atom and microcavity system, the spontaneous emission rate of an atom will be enhanced under the action of a resonant cavity, and its spontaneous emission rate is greater than that of the atom in free space.

[0043] In the field of quantum computers, the performance of a quantum computer is directly related to the degree of interference of qubits by external environmental noise. To reduce the interference of external environmental noise on qubits, the qubits are fixed in a packaging box, and the packaging box is placed in an extremely low-temperature dilution refrigerator environment. Since the packaging box generally uses a metal material, the packaging box can be equivalent to a microwave resonant cavity and affect the qubits. Specifically, it is the internal cavity structure of the packaging box that affects the qubits. This internal cavity structure has a certain resonant frequency, that is, the resonant cavity mode. When it resonates with the qubit frequency or the detuning amount is small, it will have a greater impact on the qubits. Making a simple analogy with the reading process of qubits, the state of the qubits is read through the coupling of the reading cavity and the qubits. The Purcell effect will occur on the reading link, that is, part of the energy of the qubits will be dissipated to the external space through the reading link, resulting in the decoherence of the qubits. The resonant frequency of the internal cavity of the packaging box is analogous to the frequency of the reading cavity. When the detuning amount between the resonant frequency and the qubit frequency is small or even resonant, the energy of the qubits will be dissipated through the path formed by resonance with the packaging box, resulting in a decrease in the coherence time of the qubits. In addition, the cavity mode spreads around the entire quantum chip. After the internal cavity of the packaging box forms a coupling with the XY control lines of the qubits, serious crosstalk will occur between the XY control lines of different qubits through the internal cavity of the packaging box. When a control signal is fed into the XY control line of a certain qubit, it will interfere with other qubits, making it impossible to accurately control the qubit.

[0044] As the number of qubits on a quantum chip expands, the quantum chip will become larger, which requires a larger size of the internal cavity of the packaging box. In this case, the eigenmode frequency corresponding to the internal cavity is smaller, and in a non-vacuum state of the internal cavity, its eigenmode frequency is further reduced. However, the qubit frequency is generally set in the range of 4-6 GHz. If the lowest-order mode frequency of the spatial resonance corresponding to the packaging box is lower than the frequency of one of the qubits, the higher-order modes corresponding to the packaging box will enter the qubit frequency range and affect the qubits. Therefore, in actual engineering, it is necessary to make the lowest-order mode frequency of the spatial resonance corresponding to the packaging box greater than the frequencies of all qubits in the quantum chip (the detuning amounts of the corresponding higher-order modes and the qubit frequencies are even larger), so that the cavity mode will not have an adverse impact on the qubits.

[0045] To achieve the above object, the present application discloses a quantum chip packaging box. The packaging box includes a packaging cavity defined by a first part of the box body, an annular box body part, and a second part of the box body, and is used to accommodate a quantum chip. The packaging cavity constitutes a resonant cavity described by an eigen-circuit model, and the eigen-circuit model is defined by a first inductor and a first capacitor connected in parallel. The packaging box further includes a first component equivalent to an inductor and / or a second component equivalent to a capacitor disposed inside the packaging cavity. The first component is configured to be connected in parallel with the first inductor, and the second component is configured to be connected in series with the first capacitor.

[0046] In a specific embodiment, the internal cavity of the packaging box is a cuboid or a cube. Taking the cuboid structure as an example for analysis, as Figure 3 shown, the internal cavity of the packaging box is described by a waveguide rectangular cavity model. The packaging box itself has a fixed cavity mode. The frequency calculation formula for different sub-modes of the packaging box as an eigen-circuit model is:

[0047]

[0048] where n, m, p are integers, representing different cavity modes, such as TE mode or TM mode. In this embodiment, it is the TE110 mode, and it can also be other modes. l x 、l y 、l z represent the dimensions of the internal cavity of the packaging box in a rectangular coordinate system. ∈ and μ respectively represent the permittivity and permeability of the medium in the packaging box. The larger the size of the packaging box, the smaller the frequencies of different sub-modes of the packaging box. Because the relative permittivity of the chip medium (generally silicon) (such as 11.9) is relatively large, it will cause the effective permittivity of the internal space cavity of the packaging box to be much larger than that in a vacuum state, resulting in a further decrease in the frequencies of different sub-modes of the packaging box. The qubit frequency is generally set in the range of 4 - 6 GHz. If the lowest sub-mode of the spatial resonance corresponding to the packaging box is lower than this frequency, the higher sub-modes corresponding to the packaging box will enter the qubit frequency range and affect the quantum bits. Therefore, in actual engineering, it is necessary to control the lowest sub-mode frequency of the spatial resonance corresponding to the packaging box to be greater than the frequencies of all quantum bits. The lowest sub-mode frequency is the minimum frequency after the dimensions of l x 、l y 、l z are determined under a certain set combination of integers n, m, p.

[0049] Such as Figure 4As shown, when the internal space cavity of the encapsulation box is used as a resonant cavity, it is equivalent to an LC parallel circuit, which is used as the intrinsic circuit model. Among them, the second part of the box body of the encapsulation box and the first part of the box body fixed with the quantum chip are equivalent to the two plates of the first capacitor C, and the side plate of the encapsulation box is equivalent to the first inductor L. The resonant frequency of the intrinsic circuit model satisfies Among them, the lowest-order mode frequency corresponding to the spatial resonance of the encapsulation box corresponds to a resonant frequency, and the lowest-order mode frequency corresponding to the spatial resonance of the encapsulation box is equal to the resonant frequency.

[0050] In order to increase the resonant frequency equal to the lowest-order mode frequency, the present application is provided with a first component equivalent to an inductor and / or a second component equivalent to a capacitor inside the encapsulation cavity. The first component is configured to be connected in parallel with the first inductor, and the second component is configured to be connected in series with the first capacitor. The encapsulation box and the corresponding first component and / or second component form a new circuit model. Connecting the first component in parallel in the encapsulation box to reduce the overall L in the formula, and / or connecting the second component in series to reduce the overall capacitance of the resonant frequency, thereby reducing the product value of the overall capacitance and the overall inductance in to increase the resonant frequency, so that the resonant frequency defined by the new circuit model is greater than the frequencies of all qubits in the quantum chip, that is, the lowest-order mode frequency corresponding to the spatial resonance of the encapsulation box is also greater than the frequencies of all qubits in the quantum chip.

[0051] In one embodiment, as Figure 5 shown, the first component is a metal protrusion disposed between the two plates of the first capacitor C in the encapsulation box. The metal protrusion is used as an inductance equivalent component. As Figure 6 shown, where the metal protrusion acts as an inductor L1 and is connected in parallel with the first inductor L. After acting on the encapsulation box, the resonant frequency of the resonant cavity corresponding to the encapsulation box is It can be seen from this formula that this solution can realize the adjustment of the resonant frequency, so as to satisfy that the lowest-order mode frequency corresponding to the spatial resonance of the encapsulation box is greater than the frequencies of all qubits in the quantum chip.

[0052] The outer edge of the quantum chip is attached to the inner side wall of the annular box body part. In this embodiment, on the basis of satisfying that the quantum chip can be installed in the encapsulation box and other conditions remain unchanged, the lowest-order mode frequency of the encapsulation box is maximized.

[0053] In one embodiment, the first component is a metal protrusion located between the first part and the second part of the box body. The metal protrusion passes through the quantum chip and is arranged around the qubits on the quantum chip. The metal protrusion passes through the quantum chip, so that it is not necessary to increase the areas of the first part and the second part of the box body of the packaging box. At the same time, the metal protrusion serves as an inductor in parallel with the first inductor L, thereby increasing the resonance frequency of the resonator. In addition, a set distance is provided between adjacent metal columns, which can effectively prevent crosstalk between the resonance signal of the packaging box and the qubit signal. Optionally, the metal protrusion is connected to the quantum chip in a grounded manner, which not only facilitates the layout of the quantum chip but also increases the resonance frequency of the packaging box. In one embodiment, the first part and the second part of the box body are respectively the upper cover plate and the bottom plate of the packaging box, and the annular box body part is the annular side plate of the packaging box.

[0054] In one embodiment, the metal protrusion is a metal column, and the metal column is vertically connected to the first part and the second part of the box body. This structure can maximize the effect of a single metal protrusion and also improve the stability between the packaging box and the quantum chip.

[0055] In one embodiment, the parameters of the first component include one or more of the number, position, cross-sectional shape, size, material, and distance between adjacent metal protrusions of the metal protrusion. The first components with different parameters are arranged to make the corresponding spatial resonance of the packaging box have different lowest-order mode frequencies.

[0056] The metal protrusion can be a metal column. In another embodiment, the cross-section of the metal protrusion is a rectangle to form a metal plate, which divides the packaging box into two regions with equal areas. At this time, the resonance frequency of the entire packaging box under the new circuit model is twice the lowest-order mode frequency under the intrinsic circuit model. The following solution takes the metal column as an example. In one embodiment, there are multiple metal columns. By adjusting the number, the inductance value of the inductance equivalent component is adjusted, so as to obtain different resonator frequencies, making the metal columns better arranged in the packaging box. Since the metal columns will pass through the quantum chip, on the premise that the lowest-order mode frequency of the corresponding spatial resonance of the packaging box is greater than the frequencies of all qubits in the quantum chip, the arrangement of multiple metal columns is better than that of a single metal column that meets the requirements in the internal space cavity of the packaging box. During the simulation process, the inductance value of the first component can be finely adjusted.

[0057] In one embodiment, the thickness parameter of the metal column is adjustable during simulation. In this embodiment, the size of the metal column is one of the parameters for adjusting the inductance value of the first component, and the cross-section of the metal column can be circular or rectangular.

[0058] In one embodiment, the material of the metal posts is one or more of indium, copper, and aluminum. The above materials can enable the metal posts to better adjust the resonant frequency of the packaging box.

[0059] In a specific solution, metal posts are arrayed on all the first parts of the box body outside the projection area of the qubit area on the first part of the box body. At positions avoiding the qubits, arraying the metal posts can adjust the inductance value of the first component to the greatest extent. As the number of qubits in the quantum chip increases, the size of the quantum chip will increase, and the size of the packaging box for packaging the quantum chip will also increase. According to the formula that the frequencies of different sub-modes of the packaging box satisfy it can be known that as the size of the packaging box increases, the frequencies of different sub-modes of the packaging box will all decrease. However, when metal posts are arrayed on all the first parts of the box body outside the projection of the quantum chip, as the size of the packaging box increases, the number of metal posts will also increase, and the resonant frequency defined by the new circuit model describing the packaging box and the corresponding first component and / or second component is greater than the frequencies of all the qubits in the quantum chip, so that the lowest sub-mode frequency satisfying the spatial resonance of the packaging box is greater than the frequencies of all the qubits in the quantum chip.

[0060] In another embodiment, a first protective film is coated on the surface of the metal protrusion. The first protective film can effectively prevent the metal protrusion from being oxidized and affecting the parameter values of the metal protrusion.

[0061] When metal posts are arranged in the packaging box, not only can the lowest sub-mode frequency satisfying the spatial resonance of the packaging box be greater than all the quantum frequencies of the quantum chip, but also because the lowest sub-mode frequency of the spatial resonance corresponding to the packaging box is different from the qubit frequency, the metal posts can prevent crosstalk between the qubits and the resonant signal of the packaging box.

[0062] In another embodiment, as Figure 7 shown, grooves are formed on the first part and / or the second part of the box body of the packaging box. The grooves serve as the second component, thereby increasing the resonant frequency of the packaging box. As Figure 8 shown, in this solution, grooves are formed on the first part and / or the second part of the box body of the packaging box. The bottom of the groove and the surface of the opposite plate body form the second component C1 and are connected in series with the first capacitor C. After acting on the packaging box, the resonant frequency of the packaging box is It can be seen from this formula that this solution can realize the adjustment of the resonant frequency, so as to satisfy that the lowest sub-mode frequency of the spatial resonance corresponding to the packaging box is greater than all the quantum frequencies of the quantum chip.

[0063] In one embodiment, the groove is located below the quantum chip, which is used to increase the distance between the quantum chip and the first part of the box body, so as to form a second component C1 to increase the frequency of the resonator.

[0064] The parameters of the second component include one or more of the relative area parameter, the relative distance parameter, and the material parameter. Different parameters of the second component are set to be applicable to the resonance frequency of the packaging box generated in different states being greater than all the quantum frequencies of the quantum chip.

[0065] In one embodiment, during the simulation process, the capacitance value of the second component is adjusted by adjusting the relative area parameter and the relative distance parameter of the groove.

[0066] In one embodiment, during the simulation process, the material in the groove is one of ceramic, vacuum, and polytetrafluoroethylene. This material can change the permittivity of the dielectric of the second component, thereby affecting the capacitance value of the second component.

[0067] In one embodiment, the inner side plate of the groove and / or the cavity is coated with a film to prevent the groove from being oxidized and affecting the parameter value of the groove.

[0068] In one embodiment, the metal protrusion and the groove are arranged at intervals, so that both the first component and the second component act on the corresponding resonator of the packaging box.

[0069] In all the above embodiments, the material used for the packaging box is one of copper, aluminum, or a combined material of copper and aluminum. The packaging box forms a closed metal structure through the first part of the box body, the second part of the box body, and the side plate, and can well protect the operating environment of the quantum chip in a low-temperature environment.

[0070] In the embodiments of the present application, the specific features, structures, materials, or characteristics described in each embodiment can be combined in a suitable manner in any one or more embodiments, and the lowest-order mode frequency of the spatial resonance corresponding to the packaging box can be adjusted. In practical applications, by setting the parameters of the metal protrusion and / or the groove and through the simulation of the simulation software, the lowest-order mode frequency of the spatial resonance corresponding to the packaging box is made greater than all the quantum frequencies of the quantum chip to determine the final form of the packaging box.

[0071] Based on the same application concept, the embodiments of the present application also propose a preparation method for a packaging box, including:

[0072] According to the qubit size and set conditions, the lowest-order mode frequency corresponding to the eigen-circuit model is obtained through simulation;

[0073] Inside a packaging box with an intrinsic circuit model, a first component and / or a second component are arranged to form a new circuit model that describes the packaging box and the corresponding first component and / or second component, and the resonant frequency defined by the new circuit model is greater than the frequencies of all qubits;

[0074] Wherein, the intrinsic circuit model includes a first capacitor and a first inductor connected in parallel, the new circuit model includes a second inductor provided by the first component and / or a second capacitor provided by the second component, and in the new circuit model, the first capacitor is connected in series with the second capacitor, and the first inductor is connected in parallel with the second inductor.

[0075] In this application, by setting the lowest-order mode frequency of the spatial resonance corresponding to the packaging box to be greater than the frequencies of all qubits, and by increasing the resonant frequency of the packaging box, when the detuning amount between the resonant frequency and the qubit frequency is large enough and no resonance occurs, the energy of the qubits will not dissipate through the path formed by resonance with the packaging box, thus avoiding the situation where the coherence time of the qubits decreases.

[0076] In one embodiment, obtaining the lowest-order mode frequency corresponding to the intrinsic circuit model through simulation according to the qubit size and set conditions includes the following steps:

[0077] Determine the size of the packaging box according to the quantum chip, as Figure 3 shown, obtain the value of the lowest-order mode frequency according to the calculation formulas of different-order mode frequencies of the intrinsic circuit model, and the calculation formulas of different-order mode frequencies are:

[0078]

[0079] Where n, m, p are integers, representing different cavity modes, such as the TE110 mode. l x 、l y 、l z represent the sizes of the internal cavity of the packaging box in a rectangular coordinate system; ∈ and μ respectively represent the permittivity and permeability of the medium in the packaging box, and the lowest-order mode frequency is the minimum value among different-order mode frequencies.

[0080] In one embodiment, determining the size of the internal space cavity of the packaging box according to the size of the quantum chip includes: obtaining the size of the outer edge of the quantum chip so that the outer edge of the quantum chip fits against the inner side wall of the annular box body, thereby determining the size of the internal space cavity of the packaging box.

[0081] This application provides an adjustment direction for setting the form and parameters of the first component and / or the second component by obtaining the lowest-order mode frequency corresponding to the intrinsic circuit model and the frequencies of all qubits, so as to achieve different lowest-order mode frequencies for the spatial resonance corresponding to the packaging box.

[0082] In one embodiment, within a packaging box having an intrinsic circuit model, setting a first component includes the following steps:

[0083] A metal protrusion is provided between the first part and the second part of the box body; the metal protrusion forms the first component L1 in parallel with the first inductor L. With respect to the resonant frequency formed by only the parallel connection of the first inductor and the first capacitor, the resonant frequency of the packaging box corresponding to the use of the first component L1 will increase, and it is satisfied that the lowest-order mode frequency of the spatial resonance corresponding to the packaging box is greater than all the quantum frequencies of the quantum chip.

[0084] In one embodiment, providing the metal protrusion between the first part and the second part of the box body includes the following steps:

[0085] A metal protrusion is provided between the first part and the second part of the box body, passing through the quantum chip and surrounding the qubit array on the quantum chip, and a set distance is provided between adjacent metal protrusions. By surrounding the qubits with the metal protrusions and setting the spacing between adjacent metal protrusions, crosstalk between the resonant signal of the packaging box and the qubit signal can also be effectively prevented.

[0086] In one of the embodiments, providing the metal protrusion between the first part and the second part of the box body further includes the following steps:

[0087] Under simulation conditions, adjusting the parameters of the first component, such that the lowest-order mode frequency of the spatial resonance corresponding to the packaging box is greater than all the quantum frequencies of the quantum chip; the parameters of the first component include one or more of the number, position, cross-sectional shape, size, material, and distance between adjacent metal protrusions of the metal protrusion. For the convenience of simulating the processing of the box, the metal protrusion is a metal column.

[0088] In one of the embodiments, within a packaging box having an intrinsic circuit model, setting a second component includes the following steps:

[0089] A groove is provided on the first part and / or the second part of the box body, and the groove forms the second component C1 in series with the first capacitor C; with respect to the resonant frequency formed by only the parallel connection of the first inductor and the first capacitor, the resonant frequency of the packaging box corresponding to the use of the second component C1 will increase, and it is satisfied that the final frequency of the lowest-order mode is above the qubit frequency range.

[0090] In one of the embodiments, providing the groove on the first part and / or the second part of the box body includes:

[0091] Under simulation conditions, grooves are provided on the first part of the box body and / or the second part of the box body as the second component. The parameters of the second component include one or more of a relative area parameter, a relative distance parameter, and a material parameter. Different parameters are set for the second component to be applicable to different states where the resonance frequency of the packaging box is greater than all the quantum frequencies of the quantum chip.

[0092] In one embodiment, the first part of the box body and the second part of the box body are correspondingly provided with a first groove and a second groove as the second component. Since the first groove and the second groove can be staggeredly arranged, multiple second capacitances are thus formed. Additionally, parameters such as the surface coating parameters, the type of coating material, and the thickness during coating at different positions of the first groove and / or the second groove can be set through simulation.

[0093] In one embodiment, in the packaging box having an intrinsic circuit model, setting the first component and / or the second component includes the following steps:

[0094] Under simulation conditions, the metal protrusions and the grooves are arranged at intervals within the packaging box; thereby enabling both the first component and the second component to act on the corresponding resonant cavity of the packaging box.

[0095] In one embodiment, by simulating, the side plate of the packaging box is equivalent to a first inductor, and the first part of the box body and the second part of the box body are equivalent to a first capacitor. After setting the first component and / or the second component inside the packaging box, the following steps are further included:

[0096] Prepare a finished product according to the simulated packaging box and fix the quantum chip inside the packaging box, thereby completing the preparation of a packaging box that meets the requirements.

[0097] Based on the same inventive concept, an embodiment of the present application further proposes a quantum processor, including the above-mentioned quantum chip packaging box and a quantum chip disposed in the packaging cavity of the packaging box. The present solution will not be elaborated for the packaging box and the quantum chip.

[0098] Based on the same inventive concept, an embodiment of the present application further proposes a quantum computer, and the quantum computer includes the above-mentioned quantum processor.

[0099] In the description of this specification, the description with reference to terms such as "some embodiments" or "examples" means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments. In addition, those skilled in the art can combine and combine the different embodiments or examples described in this specification.

[0100] The above are only the preferred embodiments of the present invention and do not impose any limitation on the present invention. Any person skilled in the art, within the scope of the technical solution of the present invention, makes any form of equivalent replacement or modification and other changes to the technical solution and technical content disclosed by the present invention, which are all within the content of the technical solution of the present invention and still fall within the protection scope of the present invention.

Claims

1. Quantum chip packaging box, including a packaging cavity for accommodating a quantum chip, the packaging cavity constituting a resonant cavity described by an eigen-circuit model, and the eigen-circuit model being defined by a first inductor and a first capacitor connected in parallel, characterized in that, It further includes a first component equivalent to an inductor and / or a second component equivalent to a capacitor disposed inside the encapsulation cavity. The first component is configured to be connected in parallel with a first inductor, and the second component is configured to be connected in series with a first capacitor.

2. The encapsulation box according to claim 1, wherein The encapsulation box includes an annular box body portion equivalent to a first inductor, and two oppositely disposed first box body portions and second box body portions equivalent to a first capacitor.

3. The encapsulation box according to claim 2, wherein, The outer edge of the quantum chip is attached to the inner sidewall of the annular box body portion.

4. The encapsulation box according to claim 2 or 3, characterized in that The first component is a metal protrusion located between the first box body portion and the second box body portion. The metal protrusion passes through the quantum chip and is arranged around the qubits on the quantum chip.

5. The encapsulation box according to claim 4, characterized in that, The metal protrusion is a metal column, and the metal column is vertically connected to the first box body portion and the second box body portion.

6. The encapsulation box according to claim 4, wherein The parameters of the first component include one or more of the number, position, cross-sectional shape, size, material, and distance between adjacent metal protrusions of the metal protrusion. The first components with different parameters are provided to enable the corresponding space resonance of the encapsulation box to have different lowest-order mode frequencies.

7. The encapsulation box according to claim 2 or 3, characterized in that, The second component is a groove formed in the first box body portion and / or the second box body portion of the encapsulation box.

8. The encapsulation box according to claim 7, characterized in that, The parameters of the second component include one or more of a relative area parameter, a relative distance parameter, and a material parameter. The second components with different parameters are provided to enable the corresponding space resonance of the encapsulation box to have different lowest-order mode frequencies.

9. The encapsulation box according to claim 1, characterized in that The surfaces of the first component and / or the second component are covered with a protective film.

10. A method for preparing a packaging box, the packaging box being used to accommodate a quantum chip, characterized in that, It includes the following steps: According to the qubit size and set conditions, obtain the lowest-order mode frequency corresponding to the intrinsic circuit model through simulation; In the encapsulation box having the intrinsic circuit model, set the first component and / or the second component, thereby forming a new circuit model describing the encapsulation box and the corresponding first component and / or second component, and the resonance frequency defined by the new circuit model is greater than the frequencies of all qubits in the quantum chip; Wherein, the intrinsic circuit model includes a first capacitor and a first inductor connected in parallel, and the new circuit model includes a second inductor provided by the first component and / or a second capacitor provided by the second component. In the new circuit model, the first capacitor is connected in series with the second capacitor, and the first inductor is connected in parallel with the second inductor.

11. The method according to claim 10, characterized in that, According to the qubit size and set conditions, obtaining the lowest-order mode frequency corresponding to the intrinsic circuit model through simulation includes the following steps: Determine the size of the internal space cavity of the encapsulation box according to the size of the quantum chip, and obtain the value of the lowest-order mode frequency according to the calculation formula of different-order mode frequencies of the intrinsic circuit model. The calculation formula of the different-order mode frequencies is: where n, m, p are integers, representing different cavity modes, and l x , l y , l z represent the dimensions of the internal space cavity of the encapsulation box in the rectangular coordinate system; the lowest-order mode frequency of the spatial resonance corresponding to the encapsulation box is the lowest frequency of the encapsulation cavity with the set dimensions; ∈ and μ respectively represent the permittivity and permeability of the medium in the encapsulation box, and the lowest-order mode frequency is the minimum value among different order mode frequencies.

12. A quantum processor, characterized in that, It includes the quantum chip encapsulation box according to any one of claims 1-9 and a quantum chip disposed in the encapsulation cavity of the encapsulation box.

13. A quantum computer, characterized in that, It includes the quantum processor according to claim 11.

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