Processing methods and electronic devices for quantum systems

Abstract

Embodiments of the present disclosure relate to a processing method, apparatus, electronic device, computer-readable storage medium, and computer program product for a quantum system. The processing method includes: obtaining a basis set for the quantum system, the basis set including a plurality of basis vectors; generating a new basis set corresponding to the basis set based on a first quantum circuit; determining Hamiltonian matrix elements based on a second quantum circuit, a third quantum circuit, and the new basis set; and performing evolution based on the Hamiltonian matrix elements. In this way, since the new basis set is generated based on the basis set and the first quantum circuit, the new basis set is composed of states prepared by a quantum computer. Such a new basis set can fully account for interactions between electrons, reducing or even avoiding sign problems. Further evolution can be performed using a quantum Monte Carlo method, thereby reducing the requirements for quantum circuit depth and improving accuracy.

Description

Technical Field

[0001] Embodiments of the present disclosure generally relate to quantum systems, and more particularly, to processing methods, apparatuses, electronic devices, computer-readable storage media, and computer program products for quantum systems. Background Art

[0002] Quantum mechanics is the discipline that describes the fundamental laws governing microscopic quantum systems. Unlike classical computers, which follow the laws of classical physics, quantum computing is based on microscopic quantum systems and applies the laws of quantum mechanics. Quantum computing involves a series of basic operations (called quantum gates), which can be used to construct complex quantum circuits. Quantum circuits can be used to transfer states of quantum systems (for example, from an initial state to a ground state).

[0003] However, quantum computing hardware is limited by noise and the depth of circuits it can execute before information is lost, resulting in less accurate results for quantum systems. Summary of the Invention

[0004] According to an exemplary embodiment of the present disclosure, a processing scheme for a quantum system is provided, which can fully consider the dynamic interactions between electrons, reduce the requirements for circuit depth, and thus improve accuracy.

[0005] In a first aspect of the present disclosure, a processing method for a quantum system is provided, comprising: obtaining a basis set for the quantum system, the basis set comprising a plurality of basis vectors; generating a new basis set corresponding to the basis set based on a first quantum circuit; determining a Hamiltonian matrix element based on a second quantum circuit, a third quantum circuit, and the new basis set; and performing evolution based on the Hamiltonian matrix element.

[0006] In a second aspect of the present disclosure, an electronic device is provided, comprising: at least one processing unit; and at least one memory, the at least one memory being coupled to the at least one processing unit and storing instructions for execution by the at least one processing unit, wherein the instructions, when executed by the at least one processing unit, cause the electronic device to perform actions, the actions comprising: obtaining a basis set of a quantum system, the basis set comprising a plurality of basis vectors; generating a new basis set corresponding to the basis set based on a first quantum circuit; determining a Hamiltonian matrix element based on a second quantum circuit, a third quantum circuit, and the new basis set; and performing evolution based on the Hamiltonian matrix element.

[0007] In a third aspect of the present disclosure, an apparatus for a quantum system is provided, comprising: an acquisition module configured to acquire a basis set of the quantum system, the basis set comprising a plurality of basis vectors; a generation module configured to generate a new basis set corresponding to the basis set based on a first quantum circuit; a determination module configured to determine a Hamiltonian matrix element based on a second quantum circuit, a third quantum circuit, and the new basis set; and an evolution module configured to perform evolution based on the Hamiltonian matrix element.

[0008] In a fourth aspect of the present disclosure, a computer-readable storage medium is provided, which has machine-executable instructions stored thereon, and when the machine-executable instructions are executed by a device, the device can perform the method described according to the first aspect of the present disclosure.

[0009] According to a fifth aspect of the present disclosure, a computer program product is provided, comprising computer-executable instructions, wherein the computer-executable instructions implement the method described in the first aspect of the present disclosure when executed by a processor.

[0010] According to a sixth aspect of the present disclosure, an electronic device is provided, comprising: a processing circuit configured to execute the method described in the first aspect of the present disclosure.

[0011] The purpose of providing the summary of the invention section is to introduce a series of concepts in a simplified form, which will be further described in the detailed description below. The summary of the invention section is not intended to identify the key features or essential features of the present disclosure, nor is it intended to limit the scope of the present disclosure. Other features of the present disclosure will become readily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] The above and other features, advantages and aspects of the embodiments of the present disclosure will become more apparent with reference to the following detailed description in conjunction with the accompanying drawings. In the accompanying drawings, the same or similar reference numerals represent the same or similar elements, wherein:

[0013] Figure 1 A schematic diagram of the Slater determinant is shown;

[0014] Figure 2 A flowchart illustrating an example process according to an embodiment of the present disclosure is shown;

[0015] Figure 3 A schematic diagram of generating a new basis set according to an embodiment of the present disclosure is shown;

[0016] Figure 4 shows a schematic diagram of a second quantum circuit according to an embodiment of the present disclosure;

[0017] Figure 5 shows a schematic diagram of a third quantum circuit according to an embodiment of the present disclosure;

[0018] Figure 6 A block diagram illustrating an example apparatus according to an embodiment of the present disclosure; and

[0019] Figure 7 A block diagram is shown of an example device that may be used to implement embodiments of the present disclosure. DETAILED DESCRIPTION

[0020] The following describes embodiments of the present disclosure in more detail with reference to the accompanying drawings. Although certain embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be construed as limited to the embodiments described herein. Rather, these embodiments are provided to provide a more thorough and complete understanding of the present disclosure. It should be understood that the drawings and embodiments of the present disclosure are for illustrative purposes only and are not intended to limit the scope of protection of the present disclosure.

[0021] Quantum computing has developed rapidly in recent years and has the potential to reshape the fields of simulation, encryption, and combinatorial optimization of microscopic quantum systems. Below, we first refer to Table 1 to describe some basic terminology related to quantum systems.

[0022] Table 1 Terminology of quantum systems

[0023]

[0024]

[0025] Quantum computing manipulates microscopic systems at the atomic level, applying the laws of quantum mechanics to perform a series of basic operations, known as quantum gates. By constructing these basic quantum gates into complex quantum circuits, quantum measurements can be performed at the end of the circuit to obtain information about the system. One potential application of quantum computing is the simulation of microscopic quantum systems, such as chemical molecules used in catalysis and pharmaceuticals, and solid materials used in superconductors. Calculating properties such as the energy and dynamical evolution of these microscopic quantum systems can aid in drug discovery and material design.

[0026] However, quantum computing remains at a moderately large and noisy stage, currently involving significant computational effort and limited by numerous factors, including the number of qubits, noise, system coherence time, and the fidelity of executing quantum gates. In quantum computing, as the number of quantum gate operations increases (i.e., the depth of the quantum circuit increases), the accumulation of errors leads to a decrease in quantum computation accuracy. Furthermore, the interaction between the quantum system and its surroundings can also lead to the gradual loss of valid information. Therefore, achieving better results in quantum computing for practical problems remains a hot topic of research.

[0027] The ground-state energy of a quantum system is one of the keys to quantum chemistry simulations, and determining it is crucial for determining other properties of microscopic quantum systems. Quantum Monte Carlo (QMC) uses a random sampling Monte Carlo method to approximate the ground-state energy of a quantum system. However, QMC suffers from a "sign problem," which generally arises because different wanderers contribute both positive and negative quantities to the final physical quantity. The sum of the absolute values ​​of these contributions is far greater than the true magnitude of the physical quantity. Therefore, a very large number of wanderers is required to accurately estimate the positive and negative contributions, and then to obtain the precise physical quantity through the cancellation of the positive and negative contributions. Otherwise, the estimate of the physical quantity will fluctuate significantly. The Full Configuration Interaction (FCI) method can accurately solve quantum systems, but the required computing resources increase exponentially as the target system grows, making it unable to handle larger systems.

[0028] Full Configuration Interaction Quantum Monte Carlo (FCIQMC) inherits the precise nature of FCI while simultaneously introducing randomness and reducing computational resource requirements by creating and annihilating an integer number of walkers. However, FCIQMC still suffers from a "sign problem," and calculations of physical quantities like energy will exhibit significant fluctuations unless a sufficiently large number of walkers are used.

[0029] One of the relevant quantities that needs to be determined in FCIQMC is the matrix element of the Hamiltonian. The Hamiltonian (denoted as H) is a fundamental quantity that describes the energy of a quantum system. It can be mapped to a quantum computation system and expressed as a Pauli expansion, which is the sum of multiple Pauli terms, as shown in Equation (1):

[0030]

[0031] In formula (1), P k is the Pauli term, h k is the coefficient of the Pauli term, and L is the number of Pauli expansion terms.

[0032] The matrix elements of the Hamiltonian correspond to the basis set. The basis set in FCIQMC can be expressed as the Slater determinant, or called the Slater determinant basis set. The Hamiltonian matrix elements under this basis set can be effectively calculated. Figure 1 Describes a summary of the basis set. Figure 1 A schematic diagram of the electronic configuration 100 under FCIQMC is shown.

[0033] The Slater determinant can represent an electronic configuration, also known as an electronic state or electron arrangement, etc. The wave function of FCIQMC is a linear combination of various electronic configurations, where the coefficients are equivalent to weights and are generally integers. For example, Figure 1 shows the electronic configurations 110, 120, and 130. Optionally, the electronic configuration 110 can be the ground state under the mean-field approximation obtained by the Hartree-Fock method. Correspondingly, the wave function of FCIQMC can be expressed as a linear combination of the electronic configurations 110, 120, and 130, and the coefficients are 5, 2, and 2 respectively.

[0034] Exemplarily, Figure 1 the arrows in Figure 1 represent electrons, the direction of the arrows represents the spin direction of the electrons, and the horizontal lines represent the electron orbits corresponding to the energy. The orbits without arrows are empty orbits. For example,

[0035] it can be assumed that the true state of the electrons is close to a linear combination of the three electronic configurations 110, 120, and 130. For example, Figure 1 in

[0036] it is understandable that Figure 1 the illustration shown is only a schematic representation of the electronic configurations under FCIQMC and should not be construed as a limitation on the embodiments of the present disclosure. In actual scenarios, the number of electrons, the number of electron orbits, etc. can be more.

[0037] The FCIQMC algorithm follows imaginary-time evolution. As the number of evolution steps and time increase, by changing the number of walkers in each configuration, it gradually approaches the true ground state. Exemplarily, a fixed number of walkers are initially set to start from the Slater determinant obtained by Hartree-Fock (such as Figure 1 the arrangement 110 in

[0038] Each step of evolution generates new walkers according to the absolute value of the matrix element of the Hamiltonian in the basis of a single Slater determinant, or reduces / increases the coefficients of the existing electronic configurations. Finally, new electronic configurations can be obtained.

[0039] In order to at least partially address the defects in the above-mentioned technical solutions, the embodiments of the present disclosure provide a solution that combines FCIQMC with quantum computing. A new basis set is prepared based on a basis set of a single Slater determinant. The new basis set fully considers the interaction between electrons, reduces or even avoids the influence of the QMC sign problem, and at the same time, FCIQMC reduces the requirements for the depth of the quantum circuit, thereby improving the accuracy.

[0040] Figure 2 A flowchart of an example process 200 according to some embodiments of the present disclosure is shown. At block 210, a basis set for a quantum system is obtained, the basis set comprising a plurality of basis vectors. At block 220, a new basis set corresponding to the basis set is generated based on the first quantum circuit. At block 230, a Hamiltonian matrix element is determined based on the second quantum circuit, the third quantum circuit, and the new basis set. At block 240, evolution is performed based on the Hamiltonian matrix element.

[0041] In some embodiments, a basis set for a quantum system can be used to represent multiple different electronic states. In some examples, each basis vector (or simply "basis") in the basis set can be represented as a single Slater determinant. Optionally, the multiple bases are orthogonal to each other. Exemplarily, the basis set for the quantum system can be a basis set in which each basis is a single Slater determinant.

[0042] Alternatively, the basis set may be referred to as a basis set, an old basis set, a single Slater determinant basis set, etc., and the new basis set may be referred to as a new basis set, a quantum computer basis set, etc. It is understood that the terms old basis set and new basis set herein are merely illustrative and should not be construed as limiting the embodiments of the present disclosure.

[0043] In some embodiments, process 200 may further include: generating a first quantum circuit based on an initial state basis vector from a plurality of basis vectors. Optionally, the initial state basis vector may be referred to as an initial state basis, an initial state, etc., which is not limited in the present disclosure.

[0044] Specifically, the initial state basis vector can be optimized by the variational quantum eigensolver (VQE) to generate the first quantum circuit. For example, the initial state basis vector can be the ground state under the mean field obtained by the Hartree Fock method. Then, the ground state obtained by the Hartree Fock method is used as the initial state vector and optimized by the VQE algorithm to obtain the first quantum circuit. For the convenience of description, the first quantum circuit can be represented as in Represents the optimized parameters.

[0045] It should be noted that in the embodiments of the present disclosure, the first quantum circuit can also be determined by other means. For example, the first quantum circuit can be obtained through other quantum algorithms for preparing the ground state, and the present disclosure is not limited thereto.

[0046] In some embodiments of the present disclosure, the first quantum circuit can be respectively applied to the single Slater determinant basis set to obtain a new basis set. Optionally, each basis vector in the basis set can be the ground state of a single Slater determinant. For example, the basis set can be represented as {|j>}, and the corresponding new basis set can be represented as {|φ j >}.

[0047] In some examples, the new basis set can include multiple new basis vectors. It can be understood that the new basis set generated by the first quantum circuit is no longer represented as a single Slater determinant. Instead, each new basis vector in the new basis set is represented by a quantum computer, for example, it can be composed of states prepared by a quantum computer. For example, each new basis vector can be represented as the sum of multiple Slater determinants.

[0048] Figure 3 FIG. shows a schematic diagram of generating a new basis set 300 according to an embodiment of the present disclosure. In Figure 3 the illustration, the basis set includes |11110000>310, |11011000>320, and |<1110010>330. Assume that the basis vector |11110000>310 is the initial state, and the first quantum circuit generated based on this initial state is 340. Then 340 can be applied to |11110000>310, |11011000>320, and |<1110010>330, thereby obtaining multiple new basis vectors ( Figure 3 not shown in the figure), which are respectively represented as |φ1〉, |φ2〉, and |φ3〉. <00001​​​​Furthermore, based on the first quantum circuit in the embodiments of the present disclosure, if the basis set of a single Slater determinant is orthogonal, then it can be proven that the new basis set obtained is also orthogonal. In some examples, the new basis set obtained through the embodiments of the present disclosure may be referred to as a complete basis set prepared using a quantum computer, an orthogonal basis set prepared using a quantum computer, or other names, which are not limited by the present disclosure.

[0051] Additionally or alternatively, based on the new basis set, the wave function is a linear combination of the new basis set. For example, in Figure 3 In the example, the wave function can be expressed as: 10×|φ1>+1×|φ2〉+1×|φ3>, where 10, 1 and 1 are coefficients.

[0052] Based on Figure 1 Compared with the wave function of the basis set shown in FIG. 1 , the wave function based on the new basis set in the embodiment of the present disclosure may have different coefficients. For example, the coefficients may be iteratively updated during the evolution process, which is not limited in the present disclosure.

[0053] It should be noted that Figure 3 The new basis set shown is for illustration only and should not be construed as a limitation on the embodiments of the present disclosure. For example, in actual scenarios, the number of basis vectors in the basis set can be greater, the number of electrons represented by each basis vector can be greater, and the wave function coefficients of the new basis set can be other values, for example, the coefficients can be larger (e.g., on the order of millions, etc.), and the present disclosure does not limit this.

[0054] In the embodiments of the present disclosure, since the new basis set is derived based on the first quantum circuit, it is understandable that the states corresponding to the new basis set cannot be efficiently represented on a classical computer, but can be efficiently prepared on a quantum computer. Furthermore, the Hamiltonian matrix elements can be determined and evolved on a quantum computer based on the new basis set.

[0055] In some embodiments, the Hamiltonian matrix element of the new basis set can be expressed as <φ j |H|φ i >, where φ i and φ j Respectively represent the new basis set |φ i > and |φ j >. It can be understood that for two different new basis sets |φ i > and |φ j >,<φ j |H|φ i > is a non-diagonal element.

[0056] Specifically, the Hamiltonian matrix element includes a real part and an imaginary part. The real part of the Hamiltonian matrix element can be obtained based on the second quantum circuit and the new basis set, and the imaginary part of the Hamiltonian matrix element can be obtained based on the third quantum circuit and the new basis set.

[0057] In some examples, a second quantum circuit can be generated based on the new basis set, the quantum Hadamard gate, the first quantum circuit, the control gate, and the quantum NOT gate. In some examples, a third quantum circuit can be generated based on the new basis set, the quantum Hadamard gate, the first quantum circuit, the control gate, the quantum NOT gate, and the phase gate.

[0058] For example, the real part of the Hamiltonian matrix element is obtained based on the sum of multiple Pauli terms, and the imaginary part of the Hamiltonian matrix element can be obtained based on the sum of multiple Pauli terms. Based on the above formula (1), the Pauli term associated with the Hamiltonian matrix element can be expressed as <φ j |P j |φ i >, P k represents the Pauli term in the Hamiltonian decomposition. Accordingly, it can be understood that based on <φ j |P k |φ i The real part of the Hamiltonian matrix element is obtained by summing the real parts of j |P j |φ i The sum of the imaginary parts of the Hamiltonian matrix elements is obtained.

[0059] Figure 4 FIG. 4 is a schematic diagram of a second quantum circuit 400 according to an embodiment of the present disclosure. For example, the second quantum circuit 400 can be used to determine <φ j |P j |φ i >the real part of .

[0060] like Figure 4 As shown, the second quantum circuit 400 includes a first subcircuit 410 and a second subcircuit 420, wherein the first subcircuit 410 represents a single quantum bit, and the second subcircuit 420 represents multiple quantum bits, and the number of the quantum bits is equal to the first quantum circuit (i.e. ) corresponds to the number of quantum bits.

[0061] Specifically, the quantum gates in the second quantum circuit 400 may include: a quantum Hadamard gate 411, a quantum gate 421 in the first quantum circuit, and a Pauli term P k The corresponding control P k gate 422 , the conjugate transpose 423 of the quantum gate in the first quantum circuit, and a quantum NOT gate 424 .

[0062] For example, the Pauli term P in the Hamiltonian decomposition k What is executed in the quantum circuit is the control of P k Gate 422. For example, quantum NOT gate 424 is Figure 4 Shown in Indicates that a NOT operation is performed on two different positions i and j. For example, is the conjugate transpose of the gate in matrix representation, and accordingly, Figure 4 in express The conjugate transpose of . In addition, Figure 4 The dial 412 in FIG. 4 represents the measurement operation.

[0063] Figure 5 FIG. 5 shows a schematic diagram of a third quantum circuit 500 according to an embodiment of the present disclosure. For example, the third quantum circuit 500 can be used to determine 〈φ j |P k |φ i >the imaginary part.

[0064] like Figure 5 As shown, the third quantum circuit 500 includes a first sub-circuit 510 and a second sub-circuit 520, wherein the first sub-circuit 510 represents a single quantum bit, and the second sub-circuit 520 represents multiple quantum bits, and the number of the quantum bits is equal to that of the first quantum circuit (i.e. ) corresponds to the number of quantum bits.

[0065] Specifically, the quantum gates in the third quantum circuit 500 may include: a quantum Hadamard gate 511, a phase gate 512, a quantum gate 521 in the first quantum circuit, and a phase gate 513. k The corresponding control P k gate 522 , the conjugate transpose 523 of the quantum gate in the first quantum circuit, and a quantum NOT gate 524 .

[0066] For example, the Pauli term P in the Hamiltonian decomposition k What is executed in the quantum circuit is the control of P k Gate 522. For example, quantum NOT gate 524 is Figure 5 Shown in Indicates that a NOT operation is performed on two different positions i and j. For example, is the conjugate transpose of the gate in matrix representation, and accordingly, Figure 5 in express The conjugate transpose of . In addition, Figure 5 The dial 513 in the figure indicates the measurement operation.

[0067] In this way, by Figure 4 The second quantum circuit 400 and Figure 5 The third quantum circuit 500 can obtain the real and imaginary parts of the Hamiltonian matrix element. It is understandable that the control P in the second quantum circuit 400 and the third quantum circuit 500 can be changed. k Door 422 / 522 gets Each item in , and then by adding, we can get the Hamiltonian matrix element 〈φ j |H|φ i >The final result. Optionally, Figure 4 and Figure 5 Control P in k The gate 422 / 522 may be implemented as a two-bit control gate, which is not limited in the present disclosure.

[0068] Furthermore, the embodiments of the present disclosure can be evolved based on Hamiltonian matrix elements, so that as the number of steps and time increase, it can gradually approach the true ground state. Specifically, the evolution can be performed on a classical computer, for example, an evolution under the quantum Monte Carlo method can be performed. It is understandable that since the dynamic interactions between electrons are fully considered when generating a new basis set, the influence of sign problems can be reduced or even avoided when performing the evolution. And since the evolution is performed through QMC, the requirements for the depth of the quantum circuit can be reduced, thereby improving the accuracy.

[0069] Through the solution of the embodiments of the present disclosure, because the new basis set for quantum computer representation is generated based on the old basis set of single Slater determinants, the dynamic interactions between electrons are fully considered. Compared with the old basis set, it is closer to the true ground state, thereby effectively suppressing the coefficients (or weights) of most basis vectors. Furthermore, evolution based on the new basis set can effectively suppress sign issues, thereby improving accuracy.

[0070] The embodiments of the present disclosure can be applied to various fields. Taking nitrogen molecules as an example, the FCIQMC method can be first used to determine the electronic configuration of electrons in the nitrogen molecules to determine a basis set, which includes multiple basis vectors to represent multiple different electronic configurations of electrons in the nitrogen molecules. Subsequently, a first quantum circuit can be generated based on the basis vectors in the basis set corresponding to the initial state in the electronic configuration. Furthermore, a new basis set can be generated by acting on the first quantum circuit on the basis set, and the new basis set can be composed of states representing electrons in nitrogen molecules prepared by a quantum computer. Further, the Hamiltonian matrix elements can be determined and evolved on the basis of the new basis set, thereby gradually approaching the true ground state. Optionally, the new basis set includes multiple new basis vectors, each of which is represented as the sum of multiple Slater determinants.

[0071] For example, the solution of the embodiments of the present disclosure can be used on nitrogen molecules for testing. Under the same level of standard deviation, the number of wanderers required by this solution is smaller than that of existing solutions based on a single Slater determinant basis set. Specifically, in this solution, as the circuit depth of the quantum device gradually increases, the number of wanderers required tends to gradually decrease. For example, in the embodiments of the present disclosure, a new basis set consisting of a VQE shallow circuit with 24 operators can be used, and the number of wanderers required is reduced by more than 100 times compared to existing solutions.

[0072] For example, the scheme of the embodiments of the present disclosure can be used for testing on nitrogen molecules. With the same number of walkers, the standard deviation of this scheme is smaller than that of existing schemes based on a single Slater determinant basis set. For example, in the embodiments of the present disclosure, a new basis set consisting of a VQE shallow circuit with 24 operators can be used, and the standard deviation of the energy is reduced by more than 50 times compared to existing schemes.

[0073] For example, the solution of the embodiments of the present disclosure can be used on a 2×4 Hubbard model for testing. In the embodiments of the present disclosure, a new basis set consisting of 15 layers of VQE lines can be used. Compared with the existing solution based on the basis set of a single Slater determinant, the standard deviation of the energy can be reduced by about 10 times while using only 1 / 20 of the number of walkers.

[0074] The solutions of the embodiments of the present disclosure described above can combine the respective advantages of classical computing and quantum computing, allowing them to complement each other. This fusion algorithm can reduce the demand for computing resources on each platform. Specifically, this solution combines the quantum Monte Carlo method with the ground state preparation method in quantum computing. On the one hand, the quantum Monte Carlo method can reduce the need for quantum circuit depth while still obtaining an accurate basis set; on the other hand, the shallow quantum circuit can greatly reduce the number of required wanderers, thereby suppressing the sign problem.

[0075] It should be understood that in the embodiments of the present disclosure, "first", "second", "third", etc. are only used to indicate that multiple objects may be different, but at the same time do not exclude that two objects are the same, and should not be interpreted as any limitation on the embodiments of the present disclosure.

[0076] It should also be understood that the division of the modes, situations, categories and embodiments in the embodiments of the present disclosure is only for the convenience of description and should not constitute a special limitation. The features in various modes, categories, situations and embodiments can be combined with each other when it is logical.

[0077] It should also be understood that the above content is only intended to help those skilled in the art better understand the embodiments of the present disclosure, and is not intended to limit the scope of the embodiments of the present disclosure. Those skilled in the art may make various modifications, variations, or combinations based on the above content. Such modifications, variations, or combinations are also within the scope of the embodiments of the present disclosure.

[0078] It should also be understood that the description of the above content focuses on emphasizing the differences between the various embodiments, and the same or similar points can be referenced or borrowed from each other. For the sake of brevity, they will not be repeated here.

[0079] Figure 6 6 shows a schematic block diagram of an example apparatus 600 according to some embodiments of the present disclosure. Apparatus 600 may be implemented in software, hardware, or a combination of both. In some embodiments, apparatus 600 may be implemented as a quantum computer.

[0080] like Figure 6 As shown, apparatus 600 includes an acquisition module 610, a generation module 620, a determination module 630, and an evolution module 640. Acquisition module 610 is configured to acquire a basis set of a quantum system, the basis set comprising a plurality of basis vectors. Generation module 620 is configured to generate a new basis set corresponding to the basis set based on a first quantum circuit. Determination module 630 is configured to determine a Hamiltonian matrix element based on the second quantum circuit, the third quantum circuit, and the new basis set. Evolution module 640 is configured to perform evolution based on the Hamiltonian matrix element.

[0081] In some embodiments, the apparatus 600 may further include a quantum circuit generation module configured to generate a first quantum circuit based on an initial state basis vector from a plurality of basis vectors. Alternatively, the quantum circuit generation module may be configured to generate the first quantum circuit by optimizing the initial state basis vector using a variational quantum eigensolver. Alternatively, the initial state basis vector is a mean-field ground state obtained using a Hartree-Fock method.

[0082] In some embodiments, the determination module 630 is configured to determine the real part of the Hamiltonian matrix element based on the second quantum circuit and the new basis set; determine the imaginary part of the Hamiltonian matrix element based on the third quantum circuit and the new basis set; and determine the Hamiltonian matrix element based on the real part and the imaginary part.

[0083] In some embodiments, the apparatus 600 may further include a quantum circuit generation module (not shown), which may be configured to generate a second quantum circuit based on the new basis set, the quantum Hadamard gate, the first quantum circuit, the control gate, and the quantum NOT gate. In some embodiments, the quantum circuit generation module may further be configured to generate a third quantum circuit based on the new basis set, the quantum Hadamard gate, the first quantum circuit, the control gate, the quantum NOT gate, and the phase gate.

[0084] Exemplarily, each basis vector in the plurality of basis vectors is represented as a single Slater determinant. Exemplarily, each state in the new basis set is represented as a sum of a plurality of Slater determinants. Optionally, the new basis set constitutes an orthogonal basis set.

[0085] Figure 6 The device 600 can be used to achieve the above combination Figure 2 For the sake of brevity, the process 200 will not be described in detail here.

[0086] The division of modules or units in the embodiments of the present disclosure is illustrative and is merely a logical functional division. In actual implementation, other division methods may be used. Furthermore, the functional units in the disclosed embodiments may be integrated into a single unit, exist physically separately, or two or more units may be integrated into a single unit. The aforementioned integrated units may be implemented in the form of hardware or software functional units.

[0087] Figure 7 1 shows a block diagram of an example device 700 that can be used to implement embodiments of the present disclosure. It should be understood that Figure 7 The device 700 shown is merely exemplary and should not be construed as limiting the functionality and scope of the implementations described herein. For example, the device 700 can be used to perform the process 200 described above.

[0088] like Figure 7 As shown, device 700 is in the form of a general-purpose computing device. Components of computing device 700 may include, but are not limited to, one or more processors or processing units 710, memory 720, storage devices 730, one or more communication units 740, one or more input devices 750, and one or more output devices 760. Processing unit 710 may be a real or virtual processor and is capable of performing various processes according to a program stored in memory 720. In a multi-processor system, multiple processing units execute computer-executable instructions in parallel to increase the parallel processing capabilities of computing device 700.

[0089] The computing device 700 typically includes a plurality of computer storage media. Such media can be any available media accessible to the computing device 700, including but not limited to volatile and non-volatile media, removable and non-removable media. The memory 720 can be a volatile memory (e.g., registers, caches, random access memory (RAM)), a non-volatile memory (e.g., read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory), or some combination thereof. The storage device 730 can be a removable or non-removable medium and can include a machine-readable medium, such as a flash drive, a disk, or any other medium that can be used to store information and / or data (e.g., training data for training) and can be accessed within the computing device 700.

[0090] The computing device 700 may further include additional removable / non-removable, volatile / non-volatile storage media. Figure 7 As shown in FIG, a magnetic disk drive for reading from or writing to a removable, non-volatile magnetic disk (e.g., a "floppy disk") and an optical disk drive for reading from or writing to a removable, non-volatile optical disk may be provided. In these cases, each drive may be connected to a bus (not shown) by one or more data media interfaces. The memory 720 may include a computer program product 725 having one or more program modules configured to perform various methods or actions of various implementations of the present disclosure.

[0091] The communication unit 740 enables communication with other computing devices via a communication medium. Additionally, the functionality of the components of the computing device 700 can be implemented as a single computing cluster or multiple computing machines that can communicate via a communication connection. Thus, the computing device 900 can operate in a networked environment using logical connections to one or more other servers, network personal computers (PCs), or other network nodes.

[0092] Input device 750 may be one or more input devices, such as a mouse, keyboard, or trackball. Output device 760 may be one or more output devices, such as a display, a speaker, or a printer. Computing device 700 may also communicate with one or more external devices (not shown) via communication unit 940, as needed. External devices such as storage devices, display devices, and the like may be used to communicate with one or more devices that allow a user to interact with computing device 700, or with any device that allows computing device 700 to communicate with one or more other computing devices (e.g., a network card, a modem, etc.). Such communication may be performed via an input / output (I / O) interface (not shown).

[0093] According to an exemplary implementation of the present disclosure, a computer-readable storage medium is provided, on which computer-executable instructions are stored, wherein the computer-executable instructions are executed by a processor to implement the method described above. According to an exemplary implementation of the present disclosure, a computer program product is also provided, which is tangibly stored on a non-transitory computer-readable medium and includes computer-executable instructions, and the computer-executable instructions are executed by a processor to implement the method described above. According to an exemplary implementation of the present disclosure, a computer program product is provided, on which a computer program is stored, and when the program is executed by a processor, the method described above is implemented.

[0094] Various aspects of the present disclosure are described herein with reference to flowcharts and / or block diagrams of methods, apparatuses, devices, and computer program products implemented according to the present disclosure. It should be understood that each block of the flowcharts and / or block diagrams, and combinations of blocks in the flowcharts and / or block diagrams, can be implemented by computer-readable program instructions.

[0095] These computer-readable program instructions can be provided to a processing unit of a general-purpose computer, a special-purpose computer, or other programmable data processing device, thereby producing a machine, such that when these instructions are executed by the processing unit of the computer or other programmable data processing device, a device is generated that implements the functions / actions specified in one or more blocks in the flowchart and / or block diagram. These computer-readable program instructions can also be stored in a computer-readable storage medium, where these instructions cause the computer, programmable data processing device, and / or other device to operate in a specific manner. Thus, the computer-readable medium storing the instructions comprises an article of manufacture that includes instructions for implementing various aspects of the functions / actions specified in one or more blocks in the flowchart and / or block diagram.

[0096] Computer-readable program instructions can be loaded onto a computer, other programmable data processing apparatus, or other device so that a series of operational steps are performed on the computer, other programmable data processing apparatus, or other device to produce a computer-implemented process, thereby causing the instructions executed on the computer, other programmable data processing apparatus, or other device to implement the functions / actions specified in one or more boxes in the flowchart and / or block diagram.

[0097] The flow charts and block diagrams in the accompanying drawings show the possible architecture, functions and operations of the systems, methods and computer program products according to multiple implementations of the present disclosure. In this regard, each box in the flow chart or block diagram can represent a part for a module, program segment or instruction, and a part for a module, program segment or instruction comprises one or more executable instructions for realizing the logical function of the specification. In some alternative implementations, the functions marked in the box can also occur in a sequence different from that marked in the accompanying drawings. For example, two continuous boxes can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each box in the block diagram and / or flow chart, and the combination of the boxes in the block diagram and / or flow chart can be realized by a special hardware-based system that performs the function or action of the specification, or can be realized by a combination of special hardware and computer instructions.

[0098] While various implementations of the present disclosure have been described above, the foregoing description is intended to be illustrative, not exhaustive, and not limited to the disclosed implementations. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described implementations. The terminology used herein is selected to best explain the principles of the implementations, their practical applications, or improvements to existing technologies, or to enable others skilled in the art to understand the various implementations disclosed herein.

Claims

1. A processing method for a quantum system, comprising: Acquire a basis set of the quantum system, wherein the basis set includes a plurality of basis vectors; generating a new basis set corresponding to the basis set based on the first quantum circuit; Determining a Hamiltonian matrix element based on the second quantum circuit, the third quantum circuit, and the new basis set; as well as Based on the evolution of the Hamiltonian matrix element, wherein the first quantum circuit, the second quantum circuit and the third quantum circuit represent different quantum gate combinations; The determination of the Hamiltonian matrix elements includes: determining a real part of the Hamiltonian matrix element based on the second quantum circuit and the new basis set; Determining an imaginary part of the Hamiltonian matrix element based on the third quantum circuit and the new basis set; and Based on the real part and the imaginary part, the Hamiltonian matrix element is determined.

2. The method according to claim 1, further comprising: The first quantum circuit is generated based on an initial state basis vector among the plurality of basis vectors.

3. The method according to claim 2, wherein generating a first quantum circuit comprises: The initial state basis vectors are optimized by a variational quantum eigensolver to generate the first quantum circuit.

4. The method according to claim 2, wherein the initial state basis vectors include a ground state under a mean field obtained by Hartree Fock.

5. The method according to claim 1, further comprising: The second quantum circuit is generated based on the new basis set, the quantum Hadamard gate, the first quantum circuit, the control gate and the quantum NOT gate.

6. The method according to claim 1, further comprising: The third quantum circuit is generated based on the new basis set, the quantum Hadamard gate, the first quantum circuit, the control gate, the quantum NOT gate and the phase gate. 7 . The method of claim 1 , wherein each basis vector in the plurality of basis vectors is represented as a single Slater determinant, and each state in the new basis set is represented as a sum of multiple Slater determinants.

8. The method according to any one of claims 1 to 7, wherein the new basis set constitutes an orthogonal basis set.

9. An electronic device comprising: at least one processing unit; at least one memory coupled to the at least one processing unit and storing instructions for execution by the at least one processing unit, the instructions, when executed by the at least one processing unit, causing the electronic device to perform actions, the actions comprising: obtaining a basis set for a quantum system, the basis set comprising a plurality of basis vectors; generating a new basis set corresponding to the basis set based on the first quantum circuit; Determining a Hamiltonian matrix element based on the second quantum circuit, the third quantum circuit, and the new basis set; and Based on the evolution of the Hamiltonian matrix element, wherein the first quantum circuit, the second quantum circuit and the third quantum circuit represent different quantum gate combinations; The determination of the Hamiltonian matrix elements includes: determining a real part of the Hamiltonian matrix element based on the second quantum circuit and the new basis set; Determining an imaginary part of the Hamiltonian matrix element based on the third quantum circuit and the new basis set; and Based on the real part and the imaginary part, the Hamiltonian matrix element is determined.

10. The electronic device according to claim 9, wherein the actions further comprise: The first quantum circuit is generated based on an initial state basis vector among the plurality of basis vectors.

11. The electronic device according to claim 10, wherein generating the first quantum circuit comprises: The initial state basis vectors are optimized by a variational quantum eigensolver to generate the first quantum circuit. 12 . The electronic device according to claim 10 , wherein the initial state basis vectors include a ground state under a mean field obtained by Hartree Fock.

13. The electronic device according to claim 9, wherein the actions further comprise: The second quantum circuit is generated based on the new basis set, the quantum Hadamard gate, the first quantum circuit, the control gate and the quantum NOT gate.

14. The electronic device according to claim 9, wherein the actions further comprise: The third quantum circuit is generated based on the new basis set, the quantum Hadamard gate, the first quantum circuit, the control gate, the quantum NOT gate and the phase gate. 15 . The electronic device of claim 9 , wherein each basis vector in the plurality of basis vectors is represented as a single Slater determinant, and each state in the new basis set is represented as a sum of a plurality of Slater determinants.

16. The electronic device according to any one of claims 9 to 15, wherein the new basis set constitutes an orthogonal basis set.

17. An apparatus for a quantum system, comprising: an acquisition module, configured to acquire a basis set of the quantum system, wherein the basis set includes a plurality of basis vectors; a generation module, configured to generate a new basis set corresponding to the basis set based on the first quantum circuit; a determination module configured to determine a Hamiltonian matrix element based on the second quantum circuit, the third quantum circuit, and the new basis set; as well as an evolution module configured to perform evolution based on the Hamiltonian matrix element, wherein the first quantum circuit, the second quantum circuit and the third quantum circuit represent different quantum gate combinations; The determining module is configured to: determining a real part of the Hamiltonian matrix element based on the second quantum circuit and the new basis set; Determining an imaginary part of the Hamiltonian matrix element based on the third quantum circuit and the new basis set; as well as Based on the real part and the imaginary part, the Hamiltonian matrix element is determined.

18. A computer-readable storage medium having a computer program stored thereon, wherein when the program is executed by a processor, the method according to any one of claims 1 to 8 is implemented.

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