Information processing device, information processing method, information processing program, and hybrid system

Abstract

To enable automatic setting of a quantum circuit when making a quantum computer perform quantum chemical computation.SOLUTION: A classical computer 110 acquires molecule information regarding molecules and sets elements of a quantum circuit including the depth of the quantum circuit according to the molecule information so as to set the quantum circuit to be used for quantum chemical computation. The classical computer 110 obtains a result of computation made based on the quantum circuit whose elements have been set.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The disclosed technology relates to an information processing apparatus, an information processing method, an information processing program, and a hybrid system.

Background Art

[0002] Conventionally, a technique for executing quantum chemistry calculations using a quantum computer is known. For example, Patent Document 1 discloses a quantum information processing method for obtaining energy derivatives using a quantum computer.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of Invention

Problem to be Solved by the Invention

[0004] By the way, when executing quantum chemistry calculations using a quantum computer and attempting to obtain the calculation results, the user is required to have advanced knowledge related to quantum computers. If the user does not have advanced knowledge related to quantum computers, the user cannot know what kind of quantum circuit should be set in order to obtain the desired quantum chemistry calculation results, and there is a problem that it is difficult to make the quantum computer execute the quantum chemistry calculations.

[0005] The disclosed technology has been made in view of the above circumstances, and an object thereof is to provide an information processing apparatus, an information processing method, an information processing program, and a hybrid system that can make a quantum computer execute quantum chemistry calculations even when a user does not have advanced knowledge related to quantum computers.

Means for Solving the Problem

[0006] A program according to a first aspect of this disclosure is a program to be executed by one or more computer processors, which causes a computer processor to perform the following processes: acquire molecular information which is information relating to a molecule; set up a quantum circuit used for quantum chemical calculations by setting up elements of a quantum circuit, including the depth of the quantum circuit, based on the molecular information; and acquire the results calculated based on the quantum circuit in which the elements have been set.

[0007] An information processing device in a second aspect of the present disclosure is an information processing device comprising one or more computer processors, which acquires molecular information which is information relating to an input molecule, sets up a quantum circuit used for quantum chemical calculations by setting elements of the quantum circuit, including the depth of the quantum circuit, based on the molecular information, and acquires a result calculated based on the quantum circuit in which the elements have been set.

[0008] An information processing method in a second aspect of this disclosure is an information processing method performed by one or more computer processors, which includes: acquiring molecular information which is information relating to a molecule; setting elements of a quantum circuit, including the depth of the quantum circuit, based on the molecular information to set a quantum circuit used for quantum chemical calculations; and acquiring results calculated based on the quantum circuit in which the elements have been set. [Effects of the Invention]

[0009] According to the disclosed technology, even if the user does not have advanced knowledge of quantum computers, it will be possible to have a quantum computer perform quantum chemical calculations. [Brief explanation of the drawing]

[0010] [Figure 1] This figure shows an example of the schematic configuration of the hybrid system 100 of this embodiment. [Figure 2] This is a schematic block diagram of a computer that functions as a classical computer 110, a control unit 121, and a user terminal 130. [Figure 3] This is a diagram illustrating the method for determining quantum circuits. [Figure 4] This is a diagram to explain the depth of quantum circuits. [Figure 5] This figure shows an example of a sequence executed by the hybrid system 100 of this embodiment. [Figure 6] This is a diagram illustrating another example of quantum circuit depth. [Modes for carrying out the invention]

[0011] Embodiments of the disclosed technology will be described in detail below with reference to the drawings.

[0012] <Hybrid system 100 according to an embodiment>

[0013] Figure 1 shows a hybrid system 100 according to an embodiment. The hybrid system 100 of this embodiment includes a classical computer 110, which is an example of an information processing device, a quantum computer 120, and a user terminal 130. The classical computer 110, the quantum computer 120, and the user terminal 130 are connected via a computer network, such as an IP network, as shown in Figure 1.

[0014] In the hybrid system 100 of this embodiment, the quantum computer 120 performs a predetermined quantum chemical calculation in response to a request from the classical computer 110 and outputs the calculation result of the quantum chemical calculation to the classical computer 110. The classical computer 110 outputs the calculation result corresponding to the quantum chemical calculation to the user terminal 130. As a result, the predetermined calculation process is executed for the hybrid system 100 as a whole.

[0015] The classical computer 110 includes a communication unit 111 such as a communication interface, a processing unit 112 such as a processor or a CPU (Central Processing Unit), and an information storage unit 113 including a storage device or storage medium such as a memory or a hard disk, and is configured by executing a program for performing each process. Note that the classical computer 110 may include one or a plurality of devices or servers. In addition, the program may include one or a plurality of programs, and can be recorded on a computer-readable storage medium to be a non-transitory program product.

[0016] As an example, the quantum computer 120 generates an electromagnetic wave for irradiating at least any one of the qubits in the qubit group 123 based on the information transmitted from the classical computer 110. Then, the quantum computer 120 executes a quantum circuit by irradiating at least any one of the qubits in the qubit group 123 with the generated electromagnetic wave.

[0017] In the example of Figure 1, the quantum computer 120 is provided with a control device 121 that communicates with the classical computer 110, an electromagnetic wave generation device 122 that generates an electromagnetic wave in response to a request from the control device 121, and a qubit group 123 that is irradiated with the electromagnetic wave from the electromagnetic wave generation device 122. The electromagnetic wave generation device 122 and the qubit group 123 in the quantum computer 120 are also a QPU (Quantum Processing Unit). Note that in the present embodiment, the term "quantum computer" does not mean that no operation using classical bits is performed at all, and refers to a computer including operations using qubits.

[0018] The control device 121 is a classical computer that performs operations using classical bits, and alternatively performs part or all of the processes described in the present specification as being performed by the classical computer 110.

[0019] The user terminal 130 is a classical computer that performs operations using classical bits. The user terminal 130 accepts information input by a user and executes processing according to the information.

[0020] The classical computer 110, the control device 121, and the user terminal 130 can be implemented by, for example, the computer 50 shown in FIG. 2. The computer 50 includes a central processing unit (CPU) 51, a memory 52 as a temporary storage area, and a non-volatile storage unit 53. The computer 50 further includes an input / output interface (I / F) 54 to which an external device, an output device and the like are connected, and a read / write (R / W) unit 55 that controls reading and writing of data with respect to a recording medium. The computer 50 further includes a network I / F 56 connected to a network such as the Internet. The CPU 51, the memory 52, the storage unit 53, the input / output I / F 54, the R / W unit 55, and the network I / F 56 are connected to one another via a bus 57.

[0021] In order to execute quantum chemistry calculations using a quantum computer, a user needs to set various calculation parameters, which requires advanced knowledge of quantum chemistry calculations. Therefore, there is a problem that it is difficult for a user who does not have sufficient knowledge of quantum chemistry calculations to make a quantum computer execute quantum chemistry calculations.

[0022] Further, even for a user who has knowledge of quantum chemistry calculations, if the user does not have advanced knowledge of quantum computers, the user cannot know what kind of quantum circuit should be set to obtain the desired quantum chemistry calculation result, and similarly, there is also a problem that it is difficult to make a quantum computer execute quantum chemistry calculations.

[0023] Therefore, the classical computer 110 of the hybrid system 100 of this embodiment enables the quantum computer to perform quantum chemical calculations even if the user does not have advanced knowledge of quantum computers. Specifically, the classical computer 110 sets up the quantum circuits necessary for performing quantum chemical calculations. A quantum circuit is a combination of quantum gates that represent operations on qubits.

[0024] Specifically, the classical computer 110 sets up a quantum circuit for performing the quantum chemical calculation desired by the user by setting the elements of the quantum circuit, including the depth of the quantum circuit, based on various information, including molecular information, input by the user. This makes it possible for users who do not have sufficient knowledge of quantum computers or quantum chemical calculations to easily perform quantum chemical calculations using a quantum computer.

[0025] Figure 3 is a diagram illustrating the various types of information necessary for generating a quantum circuit. The "Ansatz" shown in Figure 3 is a rule for forming a quantum circuit and determines the set of quantum gates that constitute the circuit. The "Quantum Circuit" shown in Figure 3 represents the quantum circuit itself. The "Molecular Information" shown in Figure 3 represents molecular information, which is information about the molecule being calculated. As shown in Figure 3, molecular information includes various types of information such as molecular structure, types of atoms contained in the molecule, and coordinates (labeled "Geometry" in Figure 3). In this embodiment, the explanation uses the example of molecular information including molecular structure, types of atoms contained in the molecule, and coordinates, but it is not limited to this. The information included in molecular information can be any information that allows for the calculation of the number of molecular orbitals. Furthermore, molecular information includes information about the basis set (labeled "Basis set" in Figure 3) and the active space (labeled "Active space" in Figure 3) necessary for quantum chemical calculations.

[0026] A basis set (labeled "Basis set" in Figure 3) is a set of functions that form the basis of atomic orbitals. The basis set is determined by the user. Note that the basis sets used in quantum chemical calculations are predetermined. Therefore, the user specifies the basis set to be used from these predetermined sets. If the user does not specify a basis set, the classical computer 110 may set a default basis set. Alternatively, the classical computer 110 may recommend a basis set depending on the calculation target, as described later. For example, if the computational cost of the calculation target is high, the classical computer 110 may recommend to the user that they choose a simpler basis set.

[0027] The active space (labeled "Active space" in Figure 3) is the space created by the molecular orbitals included in the calculation. By specifying the active space, it is possible to determine which molecular orbitals to include and exclude when solving many-body problems in quantum chemistry. Reducing the number of molecular orbitals included in the calculation lowers the computational cost but also lowers the computational accuracy. The active space is determined by the user's specification. Note that if there is no user input, the classical computer 110 may perform the calculation without any particular restrictions on degrees of freedom.

[0028] The classical computer 110 sets up various elements of the quantum circuit. This will be explained in detail below.

[0029] [Determining the Type] First, the classical computer 110 determines the type of Ansatz (labeled "Type" in Figure 3). The type of Ansatz corresponds to the type of rule for forming the quantum circuit. Specifically, the classical computer 110 determines the type of Ansatz based on the energy level of the computation target (labeled "Ground state or Excited state?" in Figure 3), which is an example of information representing the computation target of the quantum chemical calculation. Depending on the type of Ansatz, the set of quantum gates that constitute the quantum circuit is determined.

[0030] When performing quantum chemical calculations using a quantum computer, it is necessary to represent the Ansatz using quantum gates and to set up a combination of these quantum gates as a quantum circuit. The type of Ansatz required varies depending on the target of the quantum chemical calculation. Therefore, the classical computer 110 determines the required type of Ansatz and sets up the set of quantum gates within the quantum circuit according to that type of Ansatz.

[0031] For example, classical computer 110 selects an Ansatz of type 1 when the energy level being calculated is the ground state. Furthermore, classical computer 110 selects an Ansatz of type 2, which is different from type 1, when the energy level being calculated is an excited state. In this way, the type of Ansatz is predetermined according to the energy level being calculated.

[0032] For example, it is known that when the energy level being calculated is the ground state, the expansion coefficients of the wave function can be real numbers. On the other hand, it is known that when the energy level being calculated is an excited state, the expansion coefficients of the wave function must include complex numbers. For this reason, when the energy level being calculated is the ground state, the search space required is smaller than when the energy level being calculated is an excited state. Therefore, when the energy level being calculated is an excited state, the classical computer 110 selects an Ansatz belonging to the second type, which is more complex than when the energy level being calculated is the ground state.

[0033] Furthermore, the classical computer 110 may determine the type of Ansatz based on the Hamiltonian calculated from molecular information (labeled "Hamiltonian" in Figure 3) and a fermion qubit mapping (labeled "Fermion qubit mapping" in Figure 3), which is an example of pre-prepared information. Note that known methods can be used to calculate the Hamiltonian from molecular information.

[0034] For example, classical computer 110 selects an Ansatz type based on an operator that is based on the Hamiltonian (labeled "Hamiltonian" in Figure 3). The set of quantum gates that make up the quantum circuit is determined according to the selected Ansatz type.

[0035] Furthermore, for example, if it is possible to identify that a particular qubit is 0 or 1 from fermion qubit mapping (indicated as "Fermion qubit mapping" in Figure 3), then a quantum circuit can be constructed without that qubit. For this reason, the classical computer 110 selects a type of Ansatz that allows for the omission of qubits when constructing a quantum circuit. Then, the quantum circuit with the omission of qubits is determined according to the selected type of Ansatz.

[0036] As shown in Figure 3, when selecting the type of Ansatz, the energy level to be calculated (labeled "Ground state or Excited state?" in Figure 3) is a mandatory item, while the fermion qubit mapping information (labeled "Fermion qubit mapping" in Figure 3) and the Hamiltonian (labeled "Hamiltonian" in Figure 3) are optional.

[0037] Furthermore, the sequence of quantum gates included in a quantum circuit may change depending on the molecule being computed. For this reason, it may be advisable to determine the type of Ansatz based on the molecular information.

[0038] [Depth determination] Next, the classical computer 110 determines the depth of the quantum circuit (labeled "Depth" in Figure 3).

[0039] Figure 4 is a diagram illustrating the depth of a quantum circuit. Figure 4 shows a portion of the quantum circuit. In this embodiment, the depth of the quantum circuit is the number of steps in the quantum circuit calculation, which is determined based on the arrangement of the quantum gates that constitute the quantum circuit.

[0040] Figure 4 shows a quantum circuit for three qubits. |0> represents the state of the qubit, and |ψ(θ)> represents the quantum state obtained by the quantum circuit. Also, θ represents the parameter of the quantum circuit. In the example shown in Figure 4, four operational elements S1, S2, S3, and S4 are shown. Each of these four operational elements S1, S2, S3, and S4 is composed of a quantum gate. H represents an Hadamard gate, X represents an X gate (NOT gate), and CN1 and CN2 represent CNOT gates. In the example shown in Figure 4, the number of steps in the quantum circuit calculation is 4 (S1, S2, S3, S4), so the depth of the quantum circuit is 4. The classical computer 110 sets the depth of this quantum circuit based on molecular information input from the user.

[0041] Specifically, first, the classical computer 110 calculates the number of molecular orbitals (labeled "Number of orbitals" in Figure 3) based on molecular information, for example, by using known methods. The number of molecular orbitals can be uniquely calculated from the type of molecule using known methods. Therefore, the classical computer 110 calculates the number of molecular orbitals based on the type of molecule represented by the molecular information. Next, the classical computer 110 calculates the number of qubits required for quantum chemical calculations based on the number of molecular orbitals. Typically, twice the number of molecular orbitals is calculated as the number of qubits. Note that when determining the number of qubits, the number of qubits can also be reduced by using fermion qubit mapping (labeled "Fermion qubit mapping" in Figure 3).

[0042] The classical computer 110 then calculates the depth of the quantum circuit based on the number of qubits determined by the calculation, the required precision of the quantum chemical calculation specified by the user, and pre-prepared statistical information. The pre-prepared statistical information is based on statistics between the number of qubits and the depth of the quantum circuit. This statistical information is obtained based on past performance in quantum chemical calculations. For example, a regression equation can be used as an example of statistical information.

[0043] When using a regression equation as an example of statistical information, the classical computer 110 calculates the depth of the quantum circuit by inputting the number of qubits calculated from the number of molecular orbitals, statistical parameters based on the statistics between the number of molecular orbitals and the depth of the quantum circuit, and parameters related to the required accuracy of the quantum chemical calculation specified by the user into a pre-generated regression equation. An example of a regression equation is shown in equation (1) below.

[0044] Depth = α·x1 + β·x2 + S (1)

[0045] In the regression equation (1) above, Depth is the depth of the quantum circuit, and α and β are pre-defined statistical parameters. For example, in the regression equation (1) above, x1 is the number of qubits, and x2 is a parameter related to the required accuracy of the quantum chemical calculation. S is either a constant or a variable. If S is a constant, the depth of the quantum circuit is determined by considering variables other than the number of qubits and the required accuracy of the quantum chemical calculation.

[0046] Furthermore, since the number of qubits can be uniquely determined according to the number of molecular orbitals, the classical computer 110 may calculate the depth of the quantum circuit based on the number of molecular orbitals calculated based on molecular information and statistical information based on the relationship between the number of molecular orbitals and the depth of the quantum circuit. In this case, for example, the depth of the quantum circuit is calculated according to the following regression equation (2). In equation (2) below, z1 is the number of molecular orbitals. Also, in equation (2) below, γ is a predetermined statistical parameter.

[0047] Depth = γ·z1 + β·x2 + S (2)

[0048] Regarding quantum circuits as shown in Figure 4, when the ratio between the number of qubits and the depth of the quantum circuit is a predetermined ratio, the relationship between the accuracy and computational complexity of quantum chemical calculations is often favorable. For example, when the ratio between the number of qubits and the depth of the quantum circuit is approximately 1:1, the balance between the accuracy and computational complexity of quantum chemical calculations is often good. For this reason, a ratio of approximately 1:1 between the number of qubits and the depth of the quantum circuit is preferable. On the other hand, if the accuracy of quantum chemical calculations is to be increased, it is preferable to make the depth of the quantum circuit deeper than the number of qubits. For example, if the ratio between the number of qubits and the depth of the quantum circuit is approximately 1:1.5, highly accurate calculation results can be obtained. However, when the depth of the quantum circuit is deeper than the number of qubits, the accuracy of the quantum chemical calculations increases, but the computational complexity also increases. For this reason, when the required accuracy of the quantum chemical calculation is a general accuracy, the depth of the quantum circuit is determined by equation (1) or equation (2) above so that the ratio between the number of qubits and the depth of the quantum circuit is approximately 1:1. On the other hand, when high precision is required for quantum chemical calculations, the depth of the quantum circuit is determined such that, for example, the ratio of the number of qubits to the depth of the quantum circuit is approximately 1:1.5. It should be noted that the above ratio is merely an example. Therefore, the ratio of the number of qubits to the depth of the quantum circuit may be other than the above ratio, and could be a value such as approximately 1:1.2.

[0049] Furthermore, when determining the depth of the quantum circuit, a method other than the one described above may be used. For example, the classical computer 110 may set the depth of the quantum circuit to a first value if the required accuracy of the quantum chemical calculation is above a predetermined threshold, and set the depth of the quantum circuit to a second value if the required accuracy of the quantum chemical calculation is below the predetermined threshold. The second value is smaller than the first value. Alternatively, the depth of the quantum circuit may be determined by referring to a table that associates molecular information with the depth of the quantum circuit.

[0050] [Pattern determination] Next, the classical computer 110 determines the arrangement pattern of Ansatz's entangling gates (labeled "Pattern" in Figure 3).

[0051] The arrangement pattern of entangling gates (labeled "Pattern" in Figure 3) needs to be determined according to the type of quantum computer used for quantum chemical calculations. The arrangement pattern of entangling gates determines how the quantum circuit, determined by the method described above, is fitted into the hardware of the quantum computer.

[0052] For example, first, the classical computer 110 identifies the type of quantum computer (labeled "Connectivity of quantum device" in Figure 3) that will perform the quantum chemical calculations. For example, the classical computer 110 identifies the type of quantum computer that will perform the quantum chemical calculations based on the quantum computer information input by the user. Examples of quantum computer types include superconducting and ion trap types. Note that the quantum computer that will perform the quantum chemical calculations may include a quantum simulator using a classical computer. A quantum simulator using a classical computer is, for example, a simulator that simulates the behavior of a quantum computer on a classical computer. Then, the classical computer 110 determines the arrangement pattern of Ansatz entanglement gates (labeled "Pattern" in Figure 3) according to the type of quantum computer. The type of quantum computer and the arrangement pattern of entanglement gates are pre-associated. Therefore, the classical computer 110 determines the arrangement pattern of entanglement gates that is pre-associated with the type of quantum computer as the arrangement pattern of entanglement gates to be used.

[0053] The classical computer 110 sets up the quantum circuit (labeled "Depth" in Figure 3), the type of Ansatz element (labeled "Type" in Figure 3), and the arrangement pattern of the Ansatz entanglement gates (labeled "Pattern" in Figure 3), as determined above (labeled "Build Quantum Circuit" in Figure 3).

[0054] Setting up the quantum circuit by the classical computer 110 is equivalent to setting up the quantum circuit that the quantum computer will use to perform quantum computations. Setting up the quantum circuit also means that the classical computer 110 decides how the quantum computer should operate. Furthermore, setting up the quantum circuit also means that the classical computer 110 decides the instructions for operations on the quantum computer's qubits. Setting up the quantum circuit by the classical computer 110 also includes transmitting various information based on the quantum circuit to the quantum computer. As will be described later, the quantum computer performs quantum computations based on the quantum circuit set up by the classical computer 110 in this way.

[0055] Then, the classical computer 110 outputs a control signal to the quantum computer 120 that indicates it will execute the quantum circuit generated as described above.

[0056] The control unit 121 of the quantum computer 120 responds to a control signal output from the classical computer 110 and causes the quantum computer 120 to perform a quantum chemical calculation corresponding to the quantum circuit. The control unit 121 of the quantum computer 120 then outputs the result of the quantum chemical calculation to the classical computer 110.

[0057] The classical computer 110 obtains the results of quantum chemical calculations performed based on quantum circuits.

[0058] [Operation of the hybrid system 100 of the embodiment]

[0059] Next, the specific operation of the hybrid system 100 of the embodiment will be described. Each of the processes shown in Figure 5 is executed in each device of the hybrid system 100.

[0060] First, in step S100, the user terminal 130 transmits to the classical computer 110 the calculation target information, which is information about the calculation target, and the calculation method information, which is information about the calculation method, both of which are input by the user.

[0061] The information to be calculated includes, for example, molecular information (e.g., the types, number, and coordinates of atoms constituting the molecule), basis set, the target of the quantum chemical calculation (e.g., basis or excitation), the required precision of the quantum chemical calculation, and quantum computer information (e.g., the type of quantum computer or pseudo-quantum computer used by the user).

[0062] The calculation method information includes, for example, information about the algorithms used in quantum chemical calculations. Examples of algorithms used in quantum chemical calculations include various algorithms such as VQE (Variational Quantum Eigensolver) and SSVQE (Subspace-search variational quantum eigensolver). It should be noted that the algorithms used in quantum chemical calculations are not limited to VQE and SSVQE; various other algorithms can also be used.

[0063] Next, in step S102, the classical computer 110 receives the information to be calculated and the calculation method information transmitted from the user terminal 130.

[0064] In step S103, the classical computer 110 determines the algorithm to be used for the quantum chemical calculation based on the calculation method information received in step S102.

[0065] In this embodiment, the case in which the user determines the quantum chemistry calculation algorithm is described as an example. However, the quantum chemistry calculation algorithm may be determined from the calculation target specified by the user, rather than being determined by the user. For example, a table linking calculation targets and quantum chemistry calculation algorithms may be prepared in advance, and an algorithm that is compatible with the calculation target may be recommended. In this case, the user may select the quantum chemistry calculation algorithm to actually use from the recommended quantum chemistry calculation algorithms.

[0066] In step S104, the classical computer 110 determines the type of Ansatz (labeled "Type" in Figure 3) for determining the set of quantum gates in the quantum circuit, as described above.

[0067] In step S105, the classical computer 110 calculates the number of molecular orbitals based on the molecular information obtained in step S102, as described above, and determines the number of qubits according to that number of molecular orbitals. Also, as described above, the classical computer 110 calculates the depth of the quantum circuit (indicated as "Depth" in Figure 3) by inputting the determined number of qubits, statistical parameters, and parameters related to the required accuracy of the quantum chemical calculation obtained in step S102 into a pre-generated regression equation.

[0068] In step S106, the classical computer 110 determines the arrangement pattern of the entangling gates (labeled "Pattern" in Figure 3) based on the quantum computer information obtained in step S102, as described above.

[0069] In step S107, the classical computer 110 sets up a quantum circuit to be used for quantum chemical calculations based on the various elements set in steps S104 to S106 (labeled "Build Quantum Circuit" in Figure 3).

[0070] In step S108, the classical computer 110 transmits various information necessary for quantum chemical calculations and a control signal indicating the execution of the quantum circuit set up in step S106 to the quantum computer 120.

[0071] In step S110, the control device 121 of the quantum computer 120 receives various information and control signals transmitted from the classical computer 110 in step S108.

[0072] In step S112, the control device 121 causes the quantum computer 120 to perform quantum chemical calculations according to the various information received in step S110.

[0073] Specifically, the quantum computer 120 generates electromagnetic waves to irradiate at least one of the qubits in the qubit group 123, in accordance with the control device 121. The quantum computer 120 then irradiates at least one of the qubits in the qubit group 123 with the generated electromagnetic waves and executes a quantum circuit according to the initial information. The gate operations of each quantum gate included in the quantum circuit are converted into corresponding electromagnetic wave waveforms, and the generated electromagnetic waves are irradiated onto the qubit group 123 by the electromagnetic wave generator 122. Finally, the quantum computer 120 outputs the results of the quantum chemical calculation.

[0074] In step S114, the control device 121 transmits the result obtained in step S112 to the classical computer 110.

[0075] In step S116, the classical computer 110 receives the result transmitted from the control device 121 in step S114.

[0076] In addition, during steps S108 to S116, predetermined iterative calculations based on quantum circuits are performed between the classical computer 110 and the quantum computer 120, and results may be obtained as a result.

[0077] In step S118, the classical computer 110 transmits the result obtained in step S116, or the result obtained by processing that result, to the user terminal 130.

[0078] In step S120, the user terminal 130 receives the result transmitted from the classical computer 110.

[0079] The user terminal 130 may also be configured to display the results of the quantum chemical calculation, such as physical properties (e.g., energy) and the history of the cost function, on its own display unit (not shown). Furthermore, the user terminal 130 may also be configured to display the results of the quantum chemical calculation, such as the estimated calculation cost or the number of calculation steps, on its display unit (not shown).

[0080] Furthermore, the user terminal 130 may display information regarding the estimation of the number of qubits required, the time required for the calculation, and the number of calculation cycles on its own display unit (not shown) when performing a quantum computation. In this case, the classical computer 110 instructs the quantum computer 120 to perform a pre-prepared estimation calculation (for example, the execution of a predetermined iterative calculation). The classical computer 110 acquires a record of the iterative calculation performed by the quantum computer 120 (for example, the time required for the iterative calculation). The classical computer 110 then applies the record of the iterative calculation to a pre-prepared regression equation and predicts the time required for the actual quantum computation, taking into account the performance of the quantum computer 120. The classical computer 110 then transmits the predicted time required for the actual quantum computation to the user terminal 130. The classical computer 110 may also prepare a table that associates the performance of quantum computers with the predicted time required for the actual quantum computation, and recommend a suitable quantum computer by referring to this table.

[0081] The user checks the results displayed on the display unit (not shown) of the user terminal 130.

[0082] As described above, the classical computer in the hybrid system of the embodiment is an information processing device equipped with one or more computer processors, which acquires molecular information, which is information about the input molecule. The classical computer then sets up a quantum circuit to be used for quantum chemical calculations by setting the elements of the quantum circuit, including the depth of the quantum circuit, based on the molecular information. The classical computer then acquires the results calculated based on the quantum circuit with its elements set. This makes it possible to automatically set up the quantum circuit when having the quantum computer perform quantum chemical calculations.

[0083] Furthermore, it becomes possible to perform quantum chemical calculations using quantum computers even if the user does not possess advanced knowledge of quantum computing.

[0084] Furthermore, when performing quantum chemical calculations using a quantum computer, it is possible to optimize the balance between the accuracy and computational complexity of quantum chemical calculations by setting the depth of the quantum circuit so that the ratio between the number of qubits and the depth of the quantum circuit is a predetermined ratio.

[0085] Furthermore, by setting the depth of the quantum circuit based on the ratio between the number of qubits and the depth of the quantum circuit, it becomes possible to automate the configuration of the quantum circuit to a certain extent.

[0086] Furthermore, the technology disclosed herein is not limited to the embodiments described above, and various modifications and applications are possible without departing from the spirit of this invention.

[0087] For example, in the above embodiment, information can be transmitted and received between the classical computer 110 and the quantum computer 120 in any manner. For instance, the transmission and reception of quantum circuit parameters and measurement results between the classical computer 110 and the quantum computer 120 may be performed sequentially each time a predetermined calculation is completed, or it may be performed after all calculations have been completed.

[0088] Furthermore, although the above embodiment describes the case in which the depth of the quantum circuit is determined using a regression equation, it is not limited to this. For example, the depth of the quantum circuit may be determined using a trained model generated by a machine learning algorithm. In this case, when the number of molecular orbitals or the number of qubits and the required accuracy of the quantum chemical calculation are input to the trained model, the trained model outputs the depth of the quantum circuit. Alternatively, for example, the number of molecular orbitals or the number of qubits, the required accuracy of the quantum chemical calculation, and the depth of the quantum circuit may be associated in advance by a table, and the classical computer 110 may determine the depth of the quantum circuit by referring to that table.

[0089] Furthermore, although the above embodiment describes an example in which calculation target information is transmitted from the user terminal 130 to the classical computer 110 and the classical computer 110 performs calculations according to the calculation target information, it is not limited to this. The user terminal 130 may transmit the calculation target information to the classical computer 110 or to a storage medium or memory device accessible by the classical computer 110 via a computer network such as an IP network, or it may store the calculation target information in a storage medium or memory device and hand it over to the operator of the classical computer 110, who then inputs the calculation target information into the classical computer 110 using the storage medium or memory device.

[0090] Furthermore, although the above embodiment describes a case in which a quantum circuit is executed by irradiation with electromagnetic waves, it is not limited to this, and quantum circuits may be executed by different methods.

[0091] Furthermore, although the above embodiment describes the case in which the quantum computer 120 performs quantum chemical calculations, it is not limited to this. For example, quantum chemical calculations may be performed by a classical computer that simulates the behavior of a quantum computer.

[0092] Furthermore, although the above embodiment assumes that the classical computer 110 and the quantum computer 120 are managed by different organizations, the classical computer 110 and the quantum computer 120 may be managed as a single unit by the same organization. In this case, the transmission of quantum chemical calculation information from the classical computer 110 to the quantum computer 120 and the transmission of measurement results from the quantum computer 120 to the classical computer 110 become unnecessary. In this case, the control device 121 of the quantum computer 120 may assume the role of the classical computer 110 as described above.

[0093] Furthermore, in the above embodiment, the depth of the quantum circuit was described as the number of steps in the quantum circuit calculation determined based on the arrangement of the quantum gates constituting the quantum circuit, but it is not limited to this. For example, the depth of the quantum circuit may be the number of iterations at a predetermined quantum gate of the quantum circuit. Alternatively, a predetermined group of quantum gates may be considered as one unit, and the number of such units may be taken as the depth of the quantum circuit. For example, as shown in Figure 6, if the quantum circuit is composed of units U1, U2, and U3, the depth of the quantum circuit may be D+2, which is the sum of the number of iterations D of unit U1, the number of units U2 (1), and the number of units U3 (1). Note that in Figure 6, R Y ,R Z This represents a predetermined rotating gate.

[0094] In the embodiments described above, please note that unless the word "only" is used, such as "based only on XX," "according only to XX," or "in the case of XX only," it is assumed in this specification that additional information may also be considered. For example, the statement "do b in the case of a" does not necessarily mean "always do b in the case of a" unless explicitly stated otherwise.

[0095] Furthermore, in the embodiments described above, expressions such as "optimize" or "optimized parameters" are used. Please note that these expressions of "optimization" mean approaching the optimal state. Therefore, when attempting to obtain parameters that minimize a certain function, please note that the parameters obtained by optimizing the function may not be the global solution that minimizes the function, but rather a local solution.

[0096] Furthermore, even if there are aspects of a method, program, terminal, device, server, or system (hereinafter referred to as "method, etc.") that perform operations different from those described herein, each aspect of the disclosed technology is intended to cover the same operations as any of those described herein, and the existence of operations different from those described herein does not mean that such method, etc. is outside the scope of each aspect of the disclosed technology.

[0097] Furthermore, although the present specification describes an embodiment in which the program is pre-installed, it is also possible to provide the program by storing it on a computer-readable recording medium.

[0098] Furthermore, each component of the hybrid system in this embodiment does not have to be implemented by a single computer or server, but may be implemented in a distributed manner across multiple computers connected by a network.

[0099] For example, the processing performed by the classical computer in each of the above embodiments may be distributed and processed by multiple classical computers connected by a network. Alternatively, for example, the processing performed by the quantum computer in each of the above embodiments may be distributed and processed by multiple quantum computers connected by a network. In this case, a hybrid system is configured with at least one classical computer and at least one quantum computer. [Explanation of Symbols]

[0100] 100 Hybrid System 110 Classical Computers 111 Communications Department 112 Processing Unit 113 Information storage section 120 Quantum Computers 121 Control device 122 Electromagnetic wave generation device 123 qubit group 130 User Terminals

Claims

1. A program to be executed on one or more computer processors, We obtain molecular information, which is information about molecules. Based on the molecular information, the quantum circuit used in quantum chemical calculations is set by setting the elements of the quantum circuit, including the depth of the quantum circuit. The element obtains the result calculated based on the quantum circuit in which the element is set. A program that causes a computer processor to perform a process.

2. The depth of the quantum circuit is the number of steps in the quantum circuit calculation, which is determined based on the arrangement of the quantum gates constituting the quantum circuit. The program according to claim 1.

3. The depth of the quantum circuit is the number of repetitions of the quantum gate within the quantum circuit. The program according to claim 1.

4. The depth of the quantum circuit is calculated based on the number of molecular orbitals calculated based on the molecular information and statistical information based on the relationship between the number of molecular orbitals and the depth of the quantum circuit. The program according to claim 1.

5. Furthermore, the depth of the quantum circuit is calculated based on the required accuracy of the quantum chemical calculation specified by the user. The program according to claim 4.

6. The depth of the quantum circuit is calculated by inputting the number of molecular orbitals, statistical parameters based on the relationship between the number of molecular orbitals and the depth of the quantum circuit, and the required accuracy into a pre-generated regression equation. The program according to claim 5.

7. Based on the target of the quantum chemical calculation, the type of Ansatz used to determine the set of quantum gates in the quantum circuit is selected. The program according to claim 1.

8. Based on the Hamiltonian calculated from the molecular information, the type of Ansatz used to determine the set of quantum gates in the quantum circuit is selected. The program according to claim 1.

9. Based on the number of molecular orbitals calculated from the aforementioned molecular information, the number of qubits is determined. The program according to claim 1.

10. If the calculation target is the ground state energy, select the first type of Ansatz, If the calculation target is the energy of an excited state, select the second type of Ansatz. The program according to claim 7.

11. Based on the calculation target specified by the user, a quantum chemical calculation algorithm is selected for performing the quantum chemical calculation. The program according to claim 7.

12. An information processing device comprising one or more computer processors, We obtain molecular information, which is information about the input molecule. Based on the molecular information, the quantum circuit used in quantum chemical calculations is set by setting the elements of the quantum circuit, including the depth of the quantum circuit. The element obtains the result calculated based on the quantum circuit in which the element is set. Information processing device.

13. An information processing method performed by one or more computer processors, We obtain molecular information, which is information about molecules. Based on the molecular information, the quantum circuit used in quantum chemical calculations is set by setting the elements of the quantum circuit, including the depth of the quantum circuit. The element obtains the result calculated based on the quantum circuit in which the element is set. Information processing methods.

14. A hybrid system comprising the information processing device and quantum computer described in claim 12, The information processing device outputs a control signal to the quantum computer indicating that it will execute the quantum circuit used for quantum chemical calculations. The quantum computer, in response to the control signal, performs quantum chemical calculations corresponding to the quantum circuit, and outputs the results of the quantum chemical calculations to the information processing device. The information processing device acquires the results of the quantum chemical calculations performed based on the quantum circuit. Hybrid system.

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