Intermolecular force regulation method and quantum simulation method, device, equipment and medium

Abstract

The present invention relates to a method for regulating intermolecular forces and a quantum simulation method, device, equipment and medium, wherein the regulating method comprises: determining a first vibration frequency of a target chemical bond in a target molecule; adjusting the mirror spacing between two face-to-face reflectors arranged in an optical resonant cavity so that a second vibration frequency of the optical resonant cavity is the same as the first vibration frequency; injecting a target molecule into the optical resonant cavity; and changing the van der Waals force between target molecules by fine-tuning the mirror spacing between the two reflectors. The present invention can accurately regulate the interaction force between ions (or molecules) trapped in an ion trap, thereby improving the fidelity of quantum logic gates and the efficiency of quantum entanglement, realizing the scalability of ion trap quantum computing, and reducing crosstalk errors.

Description

Technical Field

[0001] The present invention relates to the field of quantum computing technology, and in particular to a method for regulating intermolecular forces and a quantum simulation method, device, equipment and medium. Background Art

[0002] Van der Waals forces (hereinafter referred to as van der Waals forces) are a type of weak, short-range intermolecular interaction forces. From basic physics to molecular biology, van der Waals forces play a vital role in natural sciences. Among them, the van der Waals forces between molecules are clearly manifested as a quantum phenomenon. This interaction is caused by the quantum fluctuations of electrons inside the molecule (i.e., the instantaneous motion of the electron cloud and the instantaneous formation of the dipole moment). These quantum fluctuations are irregular and constantly changing, making the electron distribution non-constant, resulting in an instantaneous dipole moment. Therefore, quantum mechanics theory can be used to comprehensively describe the van der Waals forces between molecules. In addition, compared with traditional mechanical theory, quantum mechanics theory can better describe the molecular dynamics of gases and liquids, and can establish a connection between molecular dynamics and the macroscopic properties of fluids (such as viscosity, particle diffusivity, and thermal conductivity).

[0003] On one application front, for example, the phase of condensed matter systems and the mechanical properties of multilayered two-dimensional materials can be altered by tuning the intermolecular van der Waals forces, thus offering exciting possibilities in applications such as energy storage, water harvesting, and atomic layer deposition involving chemistry and materials science.

[0004] Since electromagnetic fields can induce polarization of molecules, change the arrangement of dipole moments and thus change the van der Waals forces between molecules, current research on the manipulation and regulation of van der Waals forces is focused on electromagnetic fields, and no other methods of regulating van der Waals forces have been found.

[0005] In another application, since the ground state or excited state in the molecular vibration mode corresponds to the quantum bit 0 or 1, the molecules and their interactions can be applied to the field of quantum computing. Quantum computing is a new computing paradigm that uses quantum mechanics and quantum bits (qubits) to perform computing tasks. The superposition state and quantum entanglement state of quantum bits are two core characteristics of quantum computing. In quantum computing based on molecular bits, the internal energy level coupling of different molecules can be achieved through the van der Waals force between molecules, and then the two-bit quantum entanglement logic gate between two molecules can be realized. Therefore, it can be seen that the precise regulation of the van der Waals force between molecules is the key to realizing the quantum entanglement between molecules. However, there is currently no precise regulation method for the van der Waals force between molecules that can be applied to quantum computers, which has hindered the development of quantum computing based on molecular bits. For example, in the field of ion trap computing, in the operation of quantum gates, if the interaction force between ions (or molecules) trapped in the ion trap cannot be precisely controlled, it will lead to many errors in the operation of quantum logic gates and poor fidelity, resulting in low accuracy of quantum computing. Therefore, the precise regulation of the interaction force between ions (or molecules) is also an important problem facing the field of ion trap quantum computing. Summary of the invention

[0006] In view of the technical problems existing in the prior art, the present invention proposes a method for regulating intermolecular forces and a quantum simulation method, device, equipment and medium to provide a novel and effective method for regulating intermolecular forces.

[0007] In order to solve the above technical problems, according to one aspect of the present invention, the present invention provides a method for regulating intermolecular forces, the method comprising the following steps:

[0008] determining a first vibrational frequency of a target chemical bond in a target molecule;

[0009] Adjusting the mirror spacing between two facing reflectors in the optical resonant cavity so that a second vibration frequency of the optical resonant cavity is approximately the same as the first vibration frequency, that is, a difference between the second vibration frequency and the first vibration frequency is less than or equal to a threshold;

[0010] injecting a target molecule into the optical resonant cavity;

[0011] The van der Waals force between target molecules is changed by fine-tuning the mirror spacing between two reflective mirrors of the optical resonant cavity, wherein the van der Waals force between target molecules increases in response to an increase in the mirror spacing and decreases in response to a decrease in the mirror spacing.

[0012] Optionally, the step of determining a first vibration frequency of a target chemical bond in a target molecule comprises:

[0013] Obtaining a vibration frequency spectrum of the target molecule based on the specific spectrum, wherein the vibration frequency spectrum describes the vibration modes and vibration frequencies of different chemical bonds in the target molecule;

[0014] A vibration frequency is determined based on the vibration frequency spectrum of the target molecule as a first vibration frequency, and a chemical bond corresponding to the first vibration frequency is used as a target chemical bond.

[0015] Optionally, the specific spectrum is an infrared spectrum or a Raman spectrum.

[0016] Optionally, the method for adjusting the intermolecular forces further comprises: measuring the molecular transmission spectrum in the optical resonant cavity during the process of fine-tuning the mirror distance between two reflectors of the optical resonant cavity.

[0017] According to another aspect of the present invention, the present invention also provides a quantum simulation method for regulating intermolecular forces, comprising the following steps:

[0018] Taking two adjacent target molecules as a first quantum system, obtaining a first quantum coupling strength of the two adjacent target molecules, wherein the first quantum coupling strength is related to a first vibration frequency of a target chemical bond in the target molecule;

[0019] After injecting the target molecule into the optical resonant cavity, taking the current optical resonant cavity as a second quantum system, obtaining a second quantum coupling strength between each target molecule and the optical resonant cavity under a dissipation-free condition, wherein the second vibration frequency of the optical resonant cavity is the same as the first vibration frequency;

[0020] The total Hamiltonian of the current second quantum system is calculated based on the number of target molecules in the current optical resonant cavity, the first quantum coupling strength of two adjacent target molecules, and the second quantum coupling strength between each target molecule and the optical resonant cavity;

[0021] Solving the total Hamiltonian based on the Heisenberg equation of motion to obtain the master equation of the second quantum system under dissipation-free conditions;

[0022] Solving the master equation to obtain a transmission spectrum expression of the target molecule, wherein the input of the transmission spectrum expression is the detection light frequency, the output is the transmittance, and the parameters of the expression include the second quantum coupling intensity, the second quantum coupling intensity, the first vibration frequency of the target chemical bond, and the second vibration frequency of the optical resonant cavity;

[0023] The molecular transmission spectrum is obtained based on the transmission spectrum expression of the target molecule, which simulates the change of the van der Waals force between the target molecules caused by fine-tuning the mirror spacing between two face-to-face mirrors set in the optical resonant cavity. The van der Waals force between the target molecules increases in response to the increase of the mirror spacing, and decreases in response to the decrease of the mirror spacing.

[0024] Optionally, taking two adjacent target molecules as a first quantum system, the step of obtaining the first quantum coupling strength of the two adjacent target molecules includes:

[0025] Calculate the van der Waals potential energy between two adjacent target molecules in the first quantum system;

[0026] Treat the target molecule in the first quantum system as a spinless fermion, and obtain the fermion many-body problem;

[0027] Determine the Hamiltonian that characterizes the interaction between fermions based on fermion many-bodies;

[0028] quantizing the target chemical bond length of the target molecule based on the quantization method of intermolecular interactions; and

[0029] Based on the corresponding relationship between the Hamiltonian and the van der Waals potential and the quantized chemical bond length of the target molecule, the first quantum coupling strength of two adjacent target molecules is obtained.

[0030] Optionally, the first quantum coupling strength of two adjacent target molecules is:

[0031] ,

[0032] Among them, m1 and m2 are the masses of two adjacent target molecules, and ω1 and ω2 are the first vibration frequencies of two adjacent target chemical bonds;

[0033] The second quantum coupling intensity between each target molecule and the optical resonant cavity under dissipation-free conditions is:

[0034]

[0035] Wherein, g is the second quantum coupling strength between the nth target molecule and the optical resonant cavity, d n is the instantaneous dipole moment of the nth target molecule, , z n is the length of the nth target chemical bond to be quantized, ω n is the first vibration frequency of the nth target chemical bond, n ph is the number of photons in the optical resonant cavity, and V is the mode volume of the optical resonant cavity;

[0036] Optionally, when the target molecules injected into the optical resonant cavity are the same and the number is two, the total Hamiltonian expression of the second quantum system is:

[0037]

[0038] in, and c are the generation operator and annihilation operator of the optical resonator, respectively, ω c is the second vibration frequency of the optical resonant cavity, and g is the second quantum coupling strength between the target molecule and the optical resonant cavity; , , and are the generation operator and annihilation operator of the first and second dipoles corresponding to two adjacent target molecules, respectively; J is the first quantum coupling strength of the two adjacent target molecules;

[0039] Based on the Heisenberg equation of motion, the total Hamiltonian is solved to obtain the expression of the main equation group of the second quantum system under the dissipation-free condition:

[0040] ,

[0041] ,

[0042] ,

[0043] in, and represent the time derivatives of the first and second target molecules, respectively. and are the annihilation operators of the first and second dipoles corresponding to two adjacent target chemical bonds, respectively, ω0 is the first vibration frequency of the target chemical bond, where ω1= ω2=ω0, γ is the vibration damping of the target chemical bond, and i is an imaginary unit; represents the time derivative of the optical resonant cavity, k is the dissipation of the optical resonant cavity, c in is the detection field operator;

[0044] Solving the master equations, the transmission spectrum expression of the target molecule in the current optical resonant cavity is obtained as follows:

[0045]

[0046] Where T(ω) is the transmittance, , ω is the detection light frequency, J is the first quantum coupling strength between two adjacent target molecules, and g is the second quantum coupling strength between the target molecule and the optical resonant cavity.

[0047] According to another aspect of the present invention, the present invention also provides a quantum simulation device for regulating intermolecular forces, the quantum simulation device comprising:

[0048] A first quantum system building module is configured to use two adjacent target molecules as a first quantum system to obtain a first quantum coupling strength of the two adjacent target molecules, wherein the first quantum coupling strength is related to a first vibration frequency of a target chemical bond in the target molecule;

[0049] A second quantum system building module is configured to, after injecting the target molecule into the optical resonant cavity, use the current optical resonant cavity as a second quantum system to obtain a second quantum coupling strength between each target molecule and the optical resonant cavity under a dissipation-free condition, wherein the second vibration frequency of the optical resonant cavity is the same as the first vibration frequency;

[0050] A Hamiltonian building module is configured to calculate the total Hamiltonian of the current second quantum system based on the number of target molecules in the current optical resonant cavity, the first quantum coupling strength of two adjacent target molecules, and the second quantum coupling strength between each target molecule and the optical resonant cavity;

[0051] A transmission spectrum acquisition module is configured to solve the total Hamiltonian based on the Heisenberg equation of motion to obtain a master equation of the second quantum system under dissipation-free conditions; the master equation is solved to obtain a transmission spectrum expression of the target molecule, wherein the input of the transmission spectrum expression is the detection light frequency, the output is the transmittance, and the parameters of the expression include the first quantum coupling strength, the second quantum coupling strength, the first vibration frequency of the target chemical bond, and the second vibration frequency of the optical resonant cavity;

[0052] The force adjustment simulation module is configured to obtain a molecular transmission spectrum based on the transmission spectrum expression of the target molecule, and simulates the change of the van der Waals force between the target molecules caused by fine-tuning the mirror spacing between two face-to-face mirrors set in the optical resonant cavity. The van der Waals force between the target molecules increases in response to an increase in the mirror spacing, and decreases in response to a decrease in the mirror spacing.

[0053] According to another aspect of the present invention, the present invention also provides a computing device, including a processor and a memory, wherein the memory stores computer instructions, and when the processor runs the computer instructions, the aforementioned quantum simulation method for regulating intermolecular forces is executed.

[0054] According to another aspect of the present invention, the present invention also provides a computer-readable storage medium, wherein the computer-readable storage medium stores computer instructions, and when the computer instructions are executed by a processor, the aforementioned quantum simulation method for regulating intermolecular forces is executed.

[0055] The present invention can modulate the resonant frequency of chemical bonds by the cavity length of the optical resonant cavity (i.e., the mirror spacing between two face-to-face reflectors), thereby effectively and accurately adjusting the interaction between molecules. The applied equipment is simple, easy to operate during adjustment, and saves technical resources and costs. Based on the precise control method of intermolecular forces provided by the present invention, the intermolecular interaction can be adjusted by adjusting the cavity length of the optical resonant cavity according to the operation requirements of the quantum gate in quantum computing, so that the internal energy level of the molecule and the vibration of the molecule in space are coupled together to realize the quantum entanglement logic gate of the double molecular bit or multi-molecular bit. It can be seen that the present invention provides a physical realization basis for quantum computing based on molecular bits and can promote further development in this field. When applied to ion trap computers, the present invention can accurately adjust the interaction force between ions (or molecules) trapped in the ion trap, thereby improving the fidelity of the quantum logic gate and the efficiency of quantum entanglement, realizing the scalability of ion trap quantum computing, and reducing crosstalk errors. BRIEF DESCRIPTION OF THE DRAWINGS

[0056] The preferred embodiments of the present invention will be further described in detail below with reference to the accompanying drawings, wherein:

[0057] Figure 1 is a flow chart of a method for regulating intermolecular forces according to one embodiment of the present invention;

[0058] Figure 2 is a schematic diagram of the structural principle of an optical resonant cavity according to an embodiment of the present invention;

[0059] Figure 3 is a flow chart of a quantum simulation method for regulating intermolecular forces according to one embodiment of the present invention;

[0060] Figure 4 is a schematic diagram of a first transmission spectrum according to an embodiment of the present invention;

[0061] Figure 5 is a schematic diagram of a second transmission spectrum according to an embodiment of the present invention;

[0062] Figure 6 is a principle block diagram of a quantum simulation device for regulating intermolecular forces according to one embodiment of the present invention;

[0063] Figure 7 It is a block diagram of the structural principles of a computing device according to an embodiment of the present invention. DETAILED DESCRIPTION

[0064] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0065] In the following detailed description, reference may be made to the various specification drawings that are part of the present application and are used to illustrate specific embodiments of the present application. In the accompanying drawings, similar figure numerals describe substantially similar components in different figures. The various specific embodiments of the present application are described in sufficient detail below so that a person of ordinary skill in the art with relevant knowledge and skills in the art can implement the technical solutions of the present application. It should be understood that other embodiments may also be utilized or structural, logical or electrical changes may be made to the embodiments of the present application. In addition, the "first" and "second" in the names of the technical features of the present invention do not indicate ordering, but are only used to distinguish technical features with the same names.

[0066] Figure 1 is a flow chart of a method for regulating intermolecular forces according to one embodiment of the present invention, wherein the target molecule includes more than one chemical bond, and the method includes:

[0067] Step S11, determining a first vibration frequency of a target chemical bond in a target molecule.

[0068] Step S12, adjusting the distance between the mirror surfaces of two reflectors disposed face to face in the optical resonant cavity so that the second vibration frequency of the optical resonant cavity is approximately equal to the first vibration frequency.

[0069] Step S13, injecting target molecules into the optical resonant cavity.

[0070] Step S14, fine-tuning the distance between the two mirrors of the optical resonant cavity to adjust the van der Waals force between the target molecules.

[0071] In a molecule, the atoms that make up the chemical bonds or functional groups are in a state of constant vibration and have corresponding vibration frequencies. Therefore, when a probe light of a specific spectrum is used to illuminate the molecule, the molecular chemical bonds or functional groups can resonate and absorb the probe light. Different chemical bonds or functional groups have different absorption frequencies corresponding to the vibration frequencies, so these absorption frequencies can be clearly expressed at different positions on the probe spectrum, thereby obtaining the vibration frequencies of each chemical bond or functional group in the molecule.

[0072] Therefore, when determining the first vibration frequency of the target chemical bond in the target molecule in step S11, the vibration frequency spectrum of the target molecule is first obtained based on the specific spectrum, and the vibration frequency spectrum describes the vibration modes and vibration frequencies of different chemical bonds in the target molecule; a vibration frequency is determined based on the vibration frequency spectrum of the target molecule, and the chemical bond corresponding to the vibration frequency is used as the target chemical bond of the present invention, or referred to as the target chemical bond. In order to distinguish it from other vibration frequencies and simplify the description, the vibration frequency of the selected target chemical bond is referred to as the first vibration frequency ω0.

[0073] Furthermore, the specific spectrum is, for example, an infrared spectrum or a Raman spectrum.

[0074] For the optical resonant cavity in step S12, see Figure 2 , Figure 2 1 is a schematic diagram of the structural principle of an optical resonant cavity according to an embodiment of the present invention. The optical resonant cavity includes two facing coated reflectors, which are respectively embedded in the upper cover 11 and the base 12. Figure 2 The first reflector 111 and the second reflector 112 in the cavity. A gasket 113 is arranged between the first reflector 111 and the second reflector 112, and the hollow area in the middle of the gasket 113 is the active area. The upper cover 11 and the base 12 are fixed by a connecting piece. In order to facilitate the adjustment of the distance between the two reflectors, a rotatable nut 15 is arranged on the connecting piece. A molecule injection structure 13 is arranged on the top of the upper cover 11, which is connected to the molecule source through a catheter. An observation window 14 is also arranged on the top of the upper cover 11. The target molecule is injected into the active area inside the cavity through the molecular injection structure 13 through the catheter, such as the molecule 20 in the figure. The expression 1-1 of the resonant frequency of the optical resonant cavity is as follows:

[0075] 1-1

[0076] Among them, ω c is the vibration frequency of the optical resonant cavity. In order to distinguish it from other vibration frequencies and simplify the description, the vibration frequency of the optical resonant cavity is called the second vibration frequency; c is the speed of light; L is the mirror distance between the two mirrors of the optical resonant cavity, also called the cavity length.

[0077] According to expression 1-1, the optical resonant cavity forms a cavity field, and its vibration frequency is proportional to the inverse of the mirror spacing. The mirror spacing can be fine-tuned by adjusting the nut 15.

[0078] In step S12, the mirror spacing L between the two reflectors of the optical resonant cavity is adjusted, and the second vibration frequency ω of the optical resonant cavity is measured. c , so that the difference between it and the first vibration frequency ω0 is less than or equal to the threshold, so that the second vibration frequency ω cis approximately equal to the first vibration frequency ω0, that is, ω c ≈ ω0. The threshold value here can be determined according to the experimental accuracy and conditions, and the purpose is to make the second vibration frequency ω c Approximately equal to the first vibration frequency ω0.

[0079] Among them, the second vibration frequency ω is measured c There are many methods, such as laser interferometry, cavity modulation spectroscopy, beat frequency method, etc. Ordinary technicians in this field can select the corresponding measurement method according to specific experimental conditions, which will not be described here.

[0080] In step S14, in the process of fine-tuning the mirror spacing between the two reflectors of the optical resonant cavity, the intermolecular van der Waals force increases when the mirror spacing increases, and decreases when the mirror spacing decreases.

[0081] In addition, in the process of fine-tuning the mirror spacing between the two reflectors of the optical resonant cavity, the change of the intermolecular van der Waals force can be determined by measuring the molecular transmission spectrum in the optical resonant cavity. There are many methods for measuring the molecular transmission spectrum, such as Fourier transform infrared spectroscopy (FTIR), terahertz transmission spectroscopy (THz Transmission Spectroscopy), etc., which usually involve the following basic steps:

[0082] First, select a suitable light source that can cover the possible absorption wavelength range of molecules in the optical resonant cavity. Different light sources are suitable for different wavelength ranges, for example: xenon lamps or tungsten lamps are used in the ultraviolet-visible light region; infrared lamps (such as tungsten halogen lamps or blackbody radiation sources) are used in the infrared region; THz (terahertz) laser sources are used in the THz region, etc.

[0083] Then select a suitable spectrometer according to different spectral ranges and resolution requirements: such as Fourier transform infrared spectrometer (FTIR) for the infrared region and THz spectrometer for the terahertz band.

[0084] Select the appropriate detector according to the measured band, such as indium gallium arsenide detector (InGaAs) for the near-infrared region, gallium nitride (GaN) or indium antimonide (InSb) detector for the mid-infrared region, etc.

[0085] Then, measurement and data processing are performed. Specifically, a blank reference spectrum is measured first, that is, a spectrum without passing through the optical resonant cavity, and then the spectrum after passing through the optical resonant cavity is measured.

[0086] Then calculate the transmittance. Usually, the transmittance is calculated using the following expression 1-2:

[0087] T = Isample / Ireference 1-2

[0088] Wherein, T is the transmittance, Isample is the light intensity detected when measured through the optical resonant cavity, and Ireference is the light intensity detected when measured without passing through the optical resonant cavity.

[0089] Of course, the transmittance can also be further converted into absorbance A in order to analyze the absorption peak of the sample, depending on whether the conversion is needed. The conversion expression is shown in 1-3:

[0090] A=-log(T) 1-3

[0091] In order to understand the changes in the van der Waals forces between target molecules when fine-tuning the mirror spacing between the two mirrors of the optical resonant cavity, the molecular transmission spectrum in the optical resonant cavity is measured during the process of fine-tuning the mirror spacing between the two mirrors of the optical resonant cavity, including increasing the mirror spacing between the two mirrors of the optical resonant cavity and reducing the mirror spacing, and then a schematic diagram of the molecular transmission spectrum is drawn based on the measurement data.

[0092] On the other hand, the present invention also provides a quantum simulation method for regulating intermolecular forces. Figure 3 , Figure 3 This is a flow chart of a quantum simulation method for regulating intermolecular forces according to an embodiment of the present invention, which specifically includes the following steps:

[0093] Step S21, taking two adjacent target molecules as a first quantum system, obtaining a first quantum coupling strength of the two adjacent target molecules, wherein the first quantum coupling strength is related to a first vibration frequency of a target chemical bond in the target molecule.

[0094] Step S22, after injecting the target molecule into the optical resonant cavity, taking the current optical resonant cavity as a second quantum system, obtaining a second quantum coupling strength between each target molecule and the optical resonant cavity under a dissipation-free condition, wherein the second vibration frequency of the optical resonant cavity is the same as the first vibration frequency.

[0095] Step S23, calculating the total Hamiltonian of the second quantum system, that is, calculating the total Hamiltonian of the current second quantum system based on the number of target molecules in the current optical resonant cavity, the first quantum coupling strength of two adjacent target molecules, and the second quantum coupling strength between each target molecule and the optical resonant cavity.

[0096] Step S24, solving the total Hamiltonian based on the Heisenberg equation of motion to obtain the master equation of the second quantum system under dissipation-free conditions.

[0097] Step S25, solving the master equation to obtain the transmission spectrum expression of the target molecule, wherein the input of the transmission spectrum expression is the detection light frequency, the output is the transmittance, and the parameters of the expression include the second quantum coupling intensity, the second quantum coupling intensity, the first vibration frequency of the target chemical bond, and the second vibration frequency of the optical resonant cavity.

[0098] Step S26, simulating the regulation of intermolecular forces based on the molecular transmission spectrum obtained from the transmission spectrum expression, and obtaining a schematic diagram of the simulation results.

[0099] Wherein, in step S21, the van der Waals potential energy acting between two adjacent target molecules in the first quantum system is first calculated based on formula 2-1;

[0100] 2-1

[0101] Among them, V vdW is the van der Waals potential between two adjacent target molecules, ɛ0 is the vacuum dielectric constant, e is the dipole moment charge between two adjacent target molecules, z is the charge center distance between two adjacent molecules, z1 and z2 are the lengths of the target chemical bonds in the two adjacent target molecules respectively; the above-mentioned vacuum dielectric constant ɛ0, dipole moment charge e and intermolecular charge center distance z are collectively referred to as system parameters, which can be obtained through experiments or calculated using classical computational chemistry methods.

[0102] In this embodiment, the molecule is regarded as a spinless fermion to obtain the fermion many-body problem. Based on the fermion production and annihilation operator satisfying the anti-commutation relation and the fermion many-body problem of mutual attraction, the Hamiltonian can be used to characterize the interaction between dipoles, wherein the fermion production and annihilation operator satisfying the anti-commutation relation can be expressed by expression 2-2:

[0103] 2-2

[0104] The Hamiltonian is specifically shown by expression 2-3:

[0105] 2-3

[0106] are the creation operator and annihilation operator of the first and second dipole, respectively. is the reduced Planck constant, and J is the quantum coupling strength of the two dipoles. The dipole here corresponds to the target molecule. Since the Hamiltonian characterizes the interaction between dipoles, the Hamiltonian and the van der Waals potential can be considered as equivalent parameters.

[0107] Using the following quadratic quantization expression 2-4, substituting expression 2-4 into expression 2-1, and using expression 2-2 to express the quantized interaction Hamiltonian, the first quantum coupling intensity J of two adjacent target molecules shown in expression 2-5 is obtained:

[0108] 2-4

[0109] in, are the creation and annihilation operators of the nth molecule, respectively, and f n represents the quantum fluctuation amplitude operator of the nth molecule, k B is the Boltzmann constant, T is the temperature, m n is the mass of the nth molecule, ω n is the vibration frequency of the nth molecule, z n Represents the quantized representation of the target chemical bond length in the target molecule. Corresponding to this embodiment, when n corresponds to the serial numbers 1 and 2 of two adjacent target molecules, a quantized representation of the target chemical bond length of the two adjacent target molecules is obtained.

[0110] 2-5

[0111] Among them, m1 and m2 are the masses of two adjacent target molecules, and ω1 and ω2 are the first vibration frequencies of two adjacent target chemical bonds.

[0112] In step S22, after the target molecule is injected into the optical resonant cavity, a strong coupling is formed between the target molecule and the optical resonant cavity. Taking the current optical resonant cavity as the second quantum system, under the condition of no dissipation, the second quantum coupling strength g between the target molecule and the optical resonant cavity is as shown in formula 3-1:

[0113] 3-1

[0114] Wherein, g is the second quantum coupling strength between the nth target molecule and the optical resonant cavity, d n is the instantaneous dipole moment of the nth target chemical bond, d n =e·z n , z n is the quantized representation of the target chemical bond length in the nth target molecule, ω n is the first vibration frequency of the target chemical bond in the nth target molecule, n ph is the number of photons in the optical resonant cavity, and V is the mode volume of the optical resonant cavity.

[0115] From the above formula, we can see that due to n ph= 0, g ≠ 0, therefore, even if the optical resonant cavity is an empty cavity (i.e., there are no photons), the second quantum coupling intensity between the target molecule and the optical resonant cavity is still not zero. Therefore, as an embodiment, the present invention uses an empty cavity, which can be coupled to the mechanical vibration of the molecule based on the ground state mode of the electromagnetic field, reducing the operation and equipment costs. Of course, injecting a certain number of photons into the optical resonant cavity through a laser device can obtain a stronger coupling, and its coupling intensity is proportional to the square root of the number of coupled molecules, so the regulation effect will be more obvious.

[0116] In step S23, the total Hamiltonian of the current second quantum system can be obtained based on the first quantum coupling strength J between every two target molecules, the first quantum coupling strength g between each target molecule and the optical resonant cavity, and the Hamiltonian calculation method shown in Expression 2-3.

[0117] Taking the current situation where there are two target molecules in the optical resonator as an example, the total Hamiltonian is shown in Expression 3-2:

[0118] 3-2

[0119] in, and c are the generation operator and annihilation operator of the optical resonator, respectively, ω c is the second vibration frequency of the optical resonant cavity, and g is the second quantum coupling strength between the target molecule and the optical resonant cavity; are the production operator and annihilation operator of two adjacent target molecules respectively; J is the first quantum coupling strength of two adjacent target molecules.

[0120] Still taking the example of two target molecules in the current optical resonant cavity, in step S24, when the same type of molecules are injected into the optical resonant cavity, the resonance frequencies of the respective target chemical bonds are equal, that is, ω1= ω2=ω0. Based on the Heisenberg equation of motion, the total Hamiltonian shown in expression 3-2 is solved to obtain the main equation of the second quantum system, which is specifically a set of equations, as shown in expressions 3-3, 3-4 and 3-5 below:

[0121] 3-3

[0122] 3-4

[0123] 3-5

[0124] in, and represent the time derivatives of the first and second target molecules, respectively. and are the annihilation operators of the first and second dipoles corresponding to two adjacent target chemical bonds, ω0 is the first vibration frequency of the target chemical bond, γ is the vibration damping of the stop chemical bond, and i is an imaginary unit; represents the time derivative of the optical resonant cavity, k is the dissipation of the optical resonant cavity, c in is the detection field operator.

[0125] After the main equation of the system is obtained, in step S25, the main equation is solved to obtain the transmission spectrum of the target molecule as shown in Expression 3-6:

[0126] 3-6

[0127] Where T(ω) is the transmittance, , ω is the detection light frequency, J is the first quantum coupling strength of two adjacent target molecules, g is the second quantum coupling strength between the target molecule and the optical resonant cavity, ω c is the second vibration frequency of the optical resonant cavity, and ω0 is the first vibration frequency of the target chemical bond in the target molecule.

[0128] Since the second vibration frequency of the optical resonant cavity can be adjusted by adjusting the mirror spacing L between the two reflectors of the optical resonant cavity, the second vibration frequency of the optical resonant cavity can be adjusted by changing the second vibration frequency ω c To simulate the adjustment of the mirror spacing between the two reflectors of the optical resonant cavity, thereby adjusting the intermolecular force of the optical resonant cavity. Specifically, while adjusting the detection light frequency, the second vibration frequency ω is changed c The size of the second vibration frequency ω c The decrease of the second vibration frequency ω c increases (corresponding to a decrease in the mirror spacing), the van der Waals forces between molecules decrease accordingly.

[0129] The above embodiment illustrates the simulation process using two target molecules as an example. It can be seen that the simulation process is also applicable to multi-molecule systems. A person skilled in the art can obtain the simulation process of a multi-molecule system through the simulation process of the above two-molecule system based on common sense in the industry.

[0130] In one embodiment, taking the molecule in the optical resonant cavity as a hydrogen molecule (the HH bond resonance frequency is about 125 THz) as an example, the transmission spectrum simulated based on Expressions 3-6 is as follows: Figure 4 and Figure 5 As shown. Among them, Figure 4 is a schematic diagram of a first transmission spectrum according to an embodiment of the present invention; Figure 5is a schematic diagram of a second transmission spectrum according to an embodiment of the present invention.

[0131] in, Figure 4 and Figure 5 The first axis of the molecular transmission spectrum is the x-axis, which represents the detection light frequency ω, the second axis is the z-axis, which represents the transmittance T(ω), and the third axis is the y-axis, which represents the first vibration frequency ω0 and the second vibration frequency ω c In this embodiment, for the convenience of illustration, the y-axis is the first vibration frequency ω0 and the second vibration frequency ω c The difference △(△=ω c -ω0) and the first vibration frequency ω0 and the ratio △ / ω0, indirectly expressing the first vibration frequency ω0 and the second vibration frequency ω c difference relationship.

[0132] exist Figure 4 In , △<0, the vibration spectrum of the target molecule moves to the left as a whole, which means that the vibration frequency of the target molecule decreases. Figure 5 In the case of △>0, the vibration spectrum of the target molecule shifts to the right as a whole, which means that the vibration frequency of the target molecule increases. This effect can be called the optical spring effect, where the molecular bond softens under the red sideband and hardens under the blue sideband.

[0133] Based on the expression 2-5 of the quantum coupling intensity J between molecules and the equivalent relationship between Hamiltonian and van der Waals potential, it can be known that when the vibration frequency of the molecular bond changes, the van der Waals potential between molecules will also be affected. When the vibration frequency of the molecular bond decreases, the molecular bond softens, and the intermolecular potential will increase. Conversely, when the vibration frequency of the molecular bond increases, the molecular bond hardens, and the intermolecular potential will decrease. According to the expression 1-1 of the resonant frequency of the optical resonant cavity, the resonant frequency of the optical resonant cavity can be changed by adjusting the distance between the two mirrors. By Figure 4 and Figure 5 It can be seen that when the mirror spacing L increases, the second vibration frequency ω c When the mirror spacing L decreases, the molecular bonds soften and the van der Waals forces between molecules increase. On the contrary, when the mirror spacing L decreases, the second vibration frequency ω c As the molecular bond increases, the van der Waals forces between molecules decrease.

[0134] In another aspect, the present invention also provides a quantum simulation device for regulating intermolecular forces, see Figure 6 , Figure 6It is a principle block diagram of a quantum simulation device for regulating intermolecular forces according to an embodiment of the present invention. In this embodiment, the quantum simulation device includes a first quantum system building module 11, a second quantum system building module 12, a Hamiltonian building module 13, a transmission spectrum acquisition module 14 and a force adjustment simulation module 15. Among them, the first quantum system building module 11 is configured to use two adjacent target molecules as the first quantum system to obtain the first quantum coupling strength of the two adjacent target molecules, wherein the first quantum coupling strength is related to the first vibration frequency of the target chemical bond in the target molecule; the second quantum system building module 12 is configured to use the current optical resonant cavity as the second quantum system after the target molecule is injected into the optical resonant cavity, and obtain the second quantum coupling strength of each target molecule and the optical resonant cavity under dissipation-free conditions, wherein the second vibration frequency of the optical resonant cavity is the same as the first vibration frequency. The Hamiltonian building module 13 is configured to calculate the total Hamiltonian of the current second quantum system based on the number of target molecules in the current optical resonant cavity, the first quantum coupling strength of the two adjacent target molecules, and the second quantum coupling strength of each target molecule and the optical resonant cavity. The transmission spectrum acquisition module 14 is configured to solve the total Hamiltonian based on the Heisenberg equation of motion to obtain the master equation of the second quantum system under dissipation-free conditions; the master equation is solved to obtain the transmission spectrum expression of the target molecule, wherein the input of the transmission spectrum expression is the detection light frequency, the output is the transmittance, and the parameters of the expression include the first quantum coupling intensity, the second quantum coupling intensity, the first vibration frequency of the target chemical bond, and the second vibration frequency of the optical resonant cavity. The force adjustment simulation module 15 is configured to simulate the change of the van der Waals force between the target molecules due to the fine adjustment of the mirror spacing between two face-to-face reflectors set in the optical resonant cavity based on the molecular transmission spectrum obtained by the transmission spectrum expression of the target molecule, and the van der Waals force between the target molecules increases in response to the increase of the mirror spacing, and decreases in response to the decrease of the mirror spacing.

[0135] Therefore, when adjusting the intermolecular van der Waals force, by measuring the molecular transmission spectrum in the optical resonant cavity during fine-tuning the distance between the two mirrors of the optical resonant cavity, it can be clearly seen that when the optical cavity structure changes (mirror spacing), the intermolecular interaction force can be effectively adjusted.

[0136] Since the coupling between the photons and the molecules is still not zero when the number of photons in the optical resonant cavity is zero, that is, when the optical resonant cavity is a dark cavity, the coupling between the photons and the molecules is still not zero, the present invention can be performed without laser conditions, thus reducing the complexity of the operation; moreover, the device structure of the optical resonant cavity is simple, and the adjustable parameter is the distance between the two reflecting mirrors, which can be achieved by rotating the nut that fixes the mirrors, and is easy to adjust; when a dark cavity is used, the whole process does not require the addition of photons, and can be completed by injecting the target molecules into the cavity, thus saving technical resources and costs.

[0137] In the field of ion trap quantum computing, in quantum gate operations, since the interaction force between ions (or charged molecules) trapped in the ion trap can be precisely controlled by the method provided by the present invention, a dual-bit quantum entangled logic gate is realized, which effectively improves the quantum entanglement efficiency and reduces the crosstalk error efficiency, thereby improving the fidelity of quantum entanglement in logic gate operations and improving the application scalability of ion trap quantum computers.

[0138] In other fields, the method provided by the present invention can modulate the resonance frequency of chemical bonds by the cavity length of the optical resonant cavity, thereby effectively regulating the interaction between molecules, and the intermolecular interaction will affect the macroscopic properties of the molecular system, such as liquid viscosity, pressure, etc.

[0139] The present invention can achieve selective coupling of specific chemical bonds by adjusting the resonant frequency of the optical resonant cavity, and achieve vibration modulation of specific chemical bonds, while keeping chemical bonds in other frequency bands unaffected. Therefore, the technical solution provided by the present invention can be used to achieve chemical catalysis in the cavity.

[0140] The physical mechanism of the present invention involves the coupling between the cavity and the molecule and the interaction between molecules, thus providing a new quantum mechanics framework and establishing a quantum mechanics theoretical system suitable for analyzing multi-body interactions of higher complexity.

[0141] In another aspect, the present invention also provides a computing device, see Figure 7 , Figure 7 1 is a block diagram of the structural principle of a computing device according to an embodiment of the present invention. Figure 7 As shown, the computing device includes a processor 601 and a memory 602 storing computer program instructions; when the processor 601 executes the computer program instructions, the aforementioned quantum simulation method is executed. In one embodiment, the computing device can be a desktop computer, a laptop computer, a tablet computer, a server, or the like.

[0142] Specifically, the processor 601 may include a central processing unit (CPU) or a graphics processing unit (GPU), or an application specific integrated circuit (ASIC), or may be configured to implement one or more integrated circuits of an embodiment of the present invention. The memory 602 may include a memory for data or instructions. For example, the memory 602 may be at least one of the following: a hard disk drive (HDD), a read-only memory (ROM), a random access memory (RAM), a floppy disk drive, a flash memory, an optical disk, a magneto-optical disk, a tape, a universal serial bus (USB) drive, or other physical / tangible memory storage device. For another example, the memory 602 includes a removable or non-removable (or fixed) medium. For another example, the memory 602 may be inside or outside the integrated gateway disaster recovery device. The memory 602 may be a non-volatile solid-state memory. In other words, the memory 602 generally includes a tangible (non-transitory) computer-readable storage medium (such as a memory device) encoded with executable instructions, wherein the stored executable instructions are executed by the processor 601 (such as executed by one or more processors), and the aforementioned quantum simulation method is executed.

[0143] In one example, Figure 7 The computing device shown may also include a communication interface 603 and a bus 610. The processor 601, the memory 602, and the communication interface 603 are connected and communicate with each other via the bus 610. The communication interface 603 is mainly used to implement communication between modules, devices, units, and / or devices in the computing device.

[0144] The bus 610 includes hardware, software or both, and can couple the components of the online data traffic billing device to each other. For example, the bus may include at least one of the following: an accelerated graphics port (AGP) or other graphics bus, an enhanced industrial standard architecture (EISA) bus, a front-side bus (FSB), a hypertransport (HT) interconnect, an industrial standard architecture (ISA) bus, an infinite bandwidth interconnect, a low pin count (LPC) bus, a memory bus, a microchannel architecture (MCA) bus, a peripheral component interconnect (PCI) bus, a PCI-Express (PCI-X) bus, a serial advanced technology attachment (SATA) bus, a video electronics standard association local (VLB) bus or other suitable bus. The bus 610 may include one or more buses. Although the embodiments of the present invention describe or show a specific bus, the embodiments of the present invention may consider any suitable bus or interconnection method.

[0145] On the other hand, an embodiment of the present invention further provides a computer-readable storage medium, on which computer program instructions are stored, and when the computer program instructions are executed by a processor, the aforementioned quantum simulation method is executed. The computer-readable storage medium is, for example, a classical computer-readable storage medium, such as a read-only memory (ROM), a random access memory (RAM), a disk storage medium device, an optical storage medium device, a flash memory device, an electrical, optical or other physical / tangible memory storage device.

[0146] The flowchart and / or block diagram of the method and system of the embodiment of the present invention are described above by way of example, and various aspects of the related aspects are described. It should be understood that each box or combination thereof in the flowchart and / or block diagram can be implemented by computer program instructions, or by dedicated hardware that performs specified functions or actions, or by a combination of dedicated hardware and computer instructions. For example, these computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing device to form a machine that enables these instructions executed by such a processor to enable the implementation of the functions / actions specified in each box or combination thereof in the flowchart and / or block diagram. Such a processor can be a general-purpose processor, a special-purpose processor, a special application processor, or a field programmable logic circuit.

[0147] The above embodiments are only used to illustrate the present invention, but not to limit the present invention. Ordinary technicians in the relevant technical field can make various changes and modifications without departing from the scope of the present invention. Therefore, all equivalent technical solutions should also fall within the scope of the present invention.

Claims

1. A method for regulating intermolecular forces, characterized in that: The method comprises: determining a first vibrational frequency of a target chemical bond in a target molecule; Adjusting the mirror spacing between two facing reflectors in the optical resonant cavity so that the second vibration frequency of the optical resonant cavity is the same as the first vibration frequency; injecting a target molecule into the optical resonant cavity; The van der Waals force between target molecules is changed by finely adjusting the mirror distance between the two reflecting mirrors. The van der Waals force between target molecules increases in response to an increase in the mirror distance, and decreases in response to a decrease in the mirror distance.

2. The method for regulating intermolecular forces according to claim 1, characterized in that: The step of determining a first vibration frequency of a target chemical bond in a target molecule comprises: Obtain the vibration frequency spectrum of the target molecule based on the specific spectrum; A vibration frequency is determined based on the vibration frequency spectrum of the target molecule as a first vibration frequency, and a chemical bond corresponding to the first vibration frequency is used as a target chemical bond.

3. The method for regulating intermolecular forces according to claim 2, characterized in that: The specific spectrum is an infrared spectrum or a Raman spectrum.

4. The method for regulating intermolecular forces according to claim 1, characterized in that: Further including: The molecular transmission spectrum in the optical resonant cavity is measured during the process of finely adjusting the mirror distance between two reflective mirrors of the optical resonant cavity.

5. A quantum simulation method for regulating intermolecular forces, characterized in that: The method comprises: Taking two adjacent target molecules as a first quantum system, obtaining a first quantum coupling strength of the two adjacent target molecules, wherein the first quantum coupling strength is related to a first vibration frequency of a target chemical bond in the target molecule; After injecting the target molecule into the optical resonant cavity, taking the current optical resonant cavity as a second quantum system, obtaining the second quantum coupling strength between each target molecule and the optical resonant cavity under a dissipation-free condition, wherein the second vibration frequency of the optical resonant cavity is the same as the first vibration frequency; The total Hamiltonian of the current second quantum system is calculated based on the number of target molecules in the current optical resonant cavity, the first quantum coupling strength of two adjacent target molecules, and the second quantum coupling strength between each target molecule and the optical resonant cavity; Solving the total Hamiltonian based on the Heisenberg equation of motion to obtain the master equation of the second quantum system under dissipation-free conditions; Solving the master equation to obtain a transmission spectrum expression of the target molecule, wherein the input of the transmission spectrum expression is the detection light frequency, the output is the transmittance, and the parameters of the expression include the first quantum coupling strength, the second quantum coupling strength, the first vibration frequency of the target chemical bond, and the second vibration frequency of the optical resonant cavity; The molecular transmission spectrum obtained based on the transmission spectrum expression of the target molecule simulates the change of the van der Waals force between the target molecules caused by fine-tuning the mirror spacing between two face-to-face mirrors arranged in the optical resonant cavity. The van der Waals force between the target molecules increases in response to an increase in the mirror spacing, and decreases in response to a decrease in the mirror spacing.

6. The quantum simulation method for regulating intermolecular forces according to claim 5, characterized in that: Taking two adjacent target molecules as a first quantum system, the step of obtaining the first quantum coupling strength of the two adjacent target molecules includes: Calculate the van der Waals potential energy between two adjacent target molecules in the first quantum system; Treat the target molecule in the first quantum system as a spinless fermion, and obtain the fermion many-body problem; Determine the Hamiltonian that characterizes the interaction between fermions based on fermion many-bodies; The target chemical bond length of the target molecule is quantized based on the quantization method of intermolecular interactions; Based on the corresponding relationship between the Hamiltonian and the van der Waals potential and the quantized chemical bond length of the target molecule, the first quantum coupling strength of two adjacent target molecules is obtained.

7. The quantum simulation method for regulating intermolecular forces according to claim 6, characterized in that: The first quantum coupling strength of two adjacent target molecules is: ， Among them, m1 and m2 are the masses of two adjacent target molecules, ω1 and ω2 are the first vibration frequencies of two adjacent target chemical bonds, ɛ0 is the vacuum dielectric constant, e is the dipole moment charge between two adjacent target molecules, and z is the charge center distance between two adjacent molecules; The second quantum coupling intensity between each target molecule and the optical resonant cavity under dissipation-free conditions is: ， Where g is the second quantum coupling strength between the nth target molecule and the optical resonant cavity, d n is the instantaneous dipole moment of the nth target molecule, , z n is the length of the nth target chemical bond to be quantized, ω n is the first vibration frequency of the nth target chemical bond, n ph is the number of photons in the optical resonant cavity, V is the mode volume of the optical resonant cavity, is the reduced Planck constant.

8. The quantum simulation method for regulating intermolecular forces according to claim 7, characterized in that: When the target molecules injected into the optical resonant cavity are the same and the number is two, the total Hamiltonian expression of the second quantum system is: ， in, and c are the creation operator and annihilation operator of the optical resonator, respectively, ω c is the second vibration frequency of the optical resonant cavity, and g is the second quantum coupling strength between the target molecule and the optical resonant cavity; are the generation operator and annihilation operator of the first and second dipoles corresponding to two adjacent target molecules, respectively; J is the first quantum coupling strength of the two adjacent target molecules; Based on the Heisenberg equation of motion, the total Hamiltonian is solved to obtain the expression of the main equation group of the second quantum system under the dissipation-free condition: in, and represent the time derivatives of the first and second target molecules, respectively. and are the annihilation operators of the first and second dipoles corresponding to two adjacent target chemical bonds, respectively, ω0 is the first vibration frequency of the target chemical bond, where ω1= ω2=ω0, γ is the vibration damping of the target chemical bond, and i is an imaginary unit; represents the time derivative of the optical resonant cavity, k is the dissipation of the optical resonant cavity, c in is the detection field operator; Solving the master equations, the transmission spectrum expression of the target molecule in the current optical resonant cavity is obtained as follows: Where T(ω) is the transmittance, , ω is the detection light frequency, J is the first quantum coupling strength between two adjacent target molecules, and g is the second quantum coupling strength between the target molecule and the optical resonant cavity.

9. A quantum simulation device for regulating intermolecular forces, characterized in that: include: A first quantum system building module is configured to use two adjacent target molecules as a first quantum system to obtain a first quantum coupling strength of the two adjacent target molecules, wherein the first quantum coupling strength is related to a first vibration frequency of a target chemical bond in the target molecule; A second quantum system building module is configured to, after injecting the target molecule into the optical resonant cavity, use the current optical resonant cavity as a second quantum system to obtain a second quantum coupling strength between each target molecule and the optical resonant cavity under a dissipation-free condition, wherein the second vibration frequency of the optical resonant cavity is the same as the first vibration frequency; A Hamiltonian building module is configured to calculate the total Hamiltonian of the current second quantum system based on the number of target molecules in the current optical resonant cavity, the first quantum coupling strength of two adjacent target molecules, and the second quantum coupling strength between each target molecule and the optical resonant cavity; A transmission spectrum acquisition module is configured to solve the total Hamiltonian based on the Heisenberg equation of motion to obtain a master equation of the second quantum system under dissipation-free conditions; the master equation is solved to obtain a transmission spectrum expression of the target molecule, wherein the input of the transmission spectrum expression is the detection light frequency, the output is the transmittance, and the parameters of the expression include the first quantum coupling strength, the second quantum coupling strength, the first vibration frequency of the target chemical bond, and the second vibration frequency of the optical resonant cavity; The force adjustment simulation module is configured to obtain a molecular transmission spectrum based on the transmission spectrum expression of the target molecule, and simulates the change of the van der Waals force between the target molecules caused by fine-tuning the mirror spacing between two face-to-face mirrors set in the optical resonant cavity. The van der Waals force between the target molecules increases in response to an increase in the mirror spacing, and decreases in response to a decrease in the mirror spacing.

10. A computing device comprising a processor and a memory, characterized in that: The memory stores computer instructions, and when the processor runs the computer instructions, it executes the quantum simulation method for regulating intermolecular forces as described in any one of claims 5 to 8.

11. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores computer instructions, which, when executed by a processor, execute the quantum simulation method for regulating intermolecular forces as described in any one of claims 5 to 8.

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