CN117892830A - Compensation method for qubit driven crosstalk, qubit compensation method and product - Google Patents
Compensation method for qubit driven crosstalk, qubit compensation method and product Download PDFInfo
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Abstract
The embodiment of the application provides a compensation method, a quantum bit compensation method and a product of quantum bit driving crosstalk, wherein the compensation method comprises the steps of obtaining driving crosstalk intensity between a target quantum bit and a neighboring quantum bit, wherein the target quantum bit is a driving quantum bit; determining an actual operation matrix of the target quantum bit according to the driving crosstalk intensity; and determining a crosstalk compensation matrix between the target quantum bit and the adjacent quantum bit according to the target superposition quantum state matrix corresponding to the target quantum bit and the actual operation matrix. Embodiments of the present application are directed to compensating for drive crosstalk between qubits.
Description
Technical Field
The embodiment of the application relates to the technical field of quantum computation, in particular to a quantum bit driving crosstalk compensation method, a quantum bit compensation method and a product.
Background
Superconducting quantum computer is one of the hot schemes for realizing quantum computation, and as a carrier for quantum information processing, the fidelity of logic operation on superconducting quantum bits directly influences the output result of superconducting quantum computation.
However, the problem of driving crosstalk exists between adjacent quantum bits, the crosstalk driven by the nearest adjacent quantum bits is derived from leakage of a microwave signal driven by a single bit to the adjacent quantum bits on a quantum chip and transverse field coupling between two adjacent quantum bits, the inter-bit crosstalk mode which is most commonly studied at present is a phase error caused by direct current crosstalk of a magnetic flux signal, and the degradation of logic operation fidelity caused by the driving crosstalk between the quantum bits is less studied.
Such drive crosstalk will cause unwanted state changes in neighboring bits, thereby adversely affecting the logical operation fidelity of the superconducting qubit.
Disclosure of Invention
The embodiment of the application provides a compensation method, a quantum bit compensation method and a product for quantum bit drive crosstalk, which aim to compensate the drive crosstalk among quantum bits.
In a first aspect, an embodiment of the present application provides a method for compensating for qubit driving crosstalk, where the method includes:
acquiring driving crosstalk intensity between a target quantum bit and a neighbor quantum bit, wherein the target quantum bit is a driven quantum bit;
Determining an actual operation matrix of the target quantum bit according to the driving crosstalk intensity;
and determining a crosstalk compensation matrix between the target quantum bit and the adjacent quantum bit according to the target superposition quantum state matrix corresponding to the target quantum bit and the actual operation matrix.
Optionally, obtaining the driving crosstalk strength between the target qubit and the neighboring qubit includes:
Initializing quantum states of the target quantum bit and the neighbor quantum bit to obtain initialized different quantum states;
Respectively acting the Brix gates of the target times for the target quantum bits in the initialized different quantum states to obtain respective corresponding actual quantum state acting results of the different quantum states;
And obtaining the driving crosstalk intensity between the target quantum bit and the adjacent quantum bit according to the crosstalk probability of the adjacent quantum bit in the actual quantum state action result corresponding to each different quantum state.
Optionally, after the brix gate of the target number of times acts on the target qubit in the initialized different quantum states respectively to obtain the respective corresponding actual quantum state acting results of the different quantum states, the method further includes:
And determining the normal generation probability of the Brix gate according to the generation probability of the target quantum state in the actual quantum state action results corresponding to the different quantum states.
Optionally, initializing quantum states of the target quantum bit and the neighboring quantum bit to obtain initialized different quantum states, including:
Designating the target qubit as q 0 and the neighboring qubit as q 1;
The quantum state arrangement of the target quantum bit and the adjacent quantum bit is |q 1q0 >;
Initializing quantum states of the target quantum bit and the neighbor quantum bit to obtain initialized different quantum states, wherein the initialized different quantum states comprise: initial quantum state |00>, initial quantum state |01>, initial quantum state |10>, and initial quantum state |11>.
Optionally, in the initialized different quantum states, respectively, acting the brix gate of the target number of times for the target quantum bit to obtain respective corresponding actual quantum state acting results of the different quantum states, including:
The Brix gate of the target times acts on the target quantum bit in the initial quantum state |00>, a corresponding actual quantum state acting result is obtained, the probability of obtaining the quantum state |01> and the probability of obtaining the quantum state |11> are determined, and the probability of obtaining the quantum state |01> is taken as the first generation probability of the target quantum state in the initial quantum state |00 >; taking the probability of the obtained quantum state |11> as a first crosstalk probability of the adjacent quantum bit in the initial quantum state |00 >;
The Brix gate of the target times acts on the target quantum bit in the initial quantum state |01>, a corresponding actual quantum state acting result is obtained, the probability of obtaining the quantum state |00> and the probability of obtaining the quantum state |10> are determined, the probability of obtaining the quantum state |00> is used as the second generation probability of the target quantum state in the initial quantum state |01>, and the probability of obtaining the quantum state |10> is used as the second crosstalk probability of the adjacent quantum bit in the initial quantum state |01 >;
The Brix gate of the target times acts on the target quantum bit in the initial quantum state |10>, a corresponding actual quantum state acting result is obtained, the probability of obtaining a quantum state |11> and the probability of obtaining a quantum state |01> are determined, the probability of obtaining the quantum state |11> is used as the third generation probability of the target quantum state in the initial quantum state |10>, and the probability of obtaining the quantum state |01> is used as the third crosstalk probability of the adjacent quantum bit in the initial quantum state |10 >;
And applying the Brix gate of the target times to the target quantum bit in the initial quantum state |11>, obtaining a corresponding actual quantum state action result, determining the probability of obtaining the quantum state |10> and the probability of obtaining the quantum state |00>, taking the probability of obtaining the quantum state |10> as the fourth generation probability of the target quantum state in the initial quantum state |11>, and taking the probability of obtaining the quantum state |00> as the fourth crosstalk probability of changing the adjacent quantum bit in the initial quantum state |11 >.
Optionally, obtaining the driving crosstalk intensity between the target qubit and the neighboring qubit according to the crosstalk probability of the neighboring qubit in the actual quantum state action result corresponding to each of the different quantum states, including:
And averaging the first crosstalk probability, the second crosstalk probability, the third crosstalk probability and the fourth crosstalk probability, and taking the average value as the driving crosstalk intensity between the target quantum bit and the adjacent quantum bit.
Optionally, determining the normal generation probability of the brix gate according to the generation probability of the target quantum state in the actual quantum state action result corresponding to each of the different quantum states includes:
And calculating the average value of the first generation probability, the second generation probability, the third generation probability and the fourth generation probability, and taking the average value as the normal generation probability of the Brix gate.
Optionally, the brix gate of the target number of times acts on the target qubit in the initial quantum state |00>, and the formula for obtaining the corresponding actual quantum state acting result is as follows:
Wherein P is an actual operation matrix corresponding to the Brix gate when driving crosstalk exists; Is the probability of quantum state |01>, is the probability of quantum state |11>, is the probability of quantum state |01>, and is the probability of quantum state |11 >.
Optionally, the brix gate of the target number of times acts on the target qubit in the initial quantum state |01>, and the formula for obtaining the corresponding actual quantum state acting result is as follows:
Wherein P is an actual operation matrix corresponding to the Brix gate when driving crosstalk exists; Is the probability of quantum state |00>, is the probability of quantum state |10>, is the probability of quantum state |00>, and is the probability of quantum state |10 >.
Optionally, the brix gate of the target number of times acts on the target qubit in the initial quantum state |10>, and the formula for obtaining the corresponding actual quantum state acting result is as follows:
Wherein P is an actual operation matrix corresponding to the Brix gate when driving crosstalk exists; Is the probability of quantum state |11>, is the probability of quantum state |01>, is the probability of quantum state |11>, and is the probability of quantum state |01 >.
Optionally, the brix gate of the target number of times acts on the target qubit in the initial quantum state |11>, and the formula for obtaining the corresponding actual quantum state acting result is as follows:
Wherein P is an actual operation matrix corresponding to the Brix gate when driving crosstalk exists; Is the probability of quantum state |10>, is the probability of quantum state |00>, is the probability of quantum state |10>, and is the probability of quantum state |00 >.
Optionally, determining the actual operation matrix of the target qubit according to the driving crosstalk intensity includes:
And determining an actual operation matrix of the target qubit according to the normal generation probability of the Brix gate and the driving crosstalk intensity.
Optionally, the actual operation matrix is:
Wherein P is an actual operation matrix corresponding to the Brix gate when driving crosstalk exists; For the normal generation probability of the brix gate,/> is the drive crosstalk intensity.
Optionally, determining, according to the target superposition quantum state matrix corresponding to the target quantum bit and the actual operation matrix, a crosstalk compensation matrix between the target quantum bit and the neighboring quantum bit includes:
Determining an actual superposition quantum state matrix according to the actual operation matrix corresponding to the Brix gate under driving crosstalk;
and calculating to obtain a crosstalk compensation matrix between the target quantum bit and the adjacent quantum bit according to the actual superposition quantum state matrix and the target superposition quantum state matrix.
Optionally, according to the actual operation matrix corresponding to the brix gate under driving crosstalk, the formula for determining the actual superposition quantum state matrix is:
Wherein P is the actual operation matrix corresponding to the brix gate under driving crosstalk, and is the actual superposition quantum state matrix.
Optionally, according to the actual superposition quantum state matrix and the target superposition quantum state matrix, a formula for calculating a crosstalk compensation matrix between the target quantum bit and the neighboring quantum bit is as follows:
the crosstalk compensation matrix A is calculated as follows:
Wherein a is a crosstalk compensation matrix between the target qubit and the neighboring qubit, is the actual stacked quantum state matrix, and/> is the target stacked quantum state matrix.
Optionally, after determining the crosstalk compensation matrix between the target qubit and the neighboring qubit according to the target superposition qustate matrix corresponding to the target qubit and the actual operation matrix, the method further includes:
and storing a crosstalk compensation matrix between the target qubit and the neighboring qubit in a compensation matrix database.
Optionally, after storing the crosstalk compensation matrix between the target qubit and the neighboring qubit in a compensation matrix database, the method further comprises:
And updating a crosstalk compensation matrix between the target qubit and the adjacent qubit stored in the compensation matrix database at preset time intervals.
In a second aspect, an embodiment of the present application provides a qubit compensation method, the method including:
Acquiring quantum bits to be operated;
Inquiring whether a crosstalk compensation matrix corresponding to the quantum bit to be operated exists in a compensation matrix database, wherein the crosstalk compensation matrix between any quantum bit and a quantum bit adjacent to the quantum bit is stored in the compensation matrix database, and the crosstalk compensation matrix between any quantum bit and the quantum bit adjacent to the quantum bit is calculated according to the quantum bit driving crosstalk compensation method according to the first aspect of the embodiment;
And if the crosstalk compensation matrix corresponding to the quantum bit to be operated exists in the compensation matrix database, after the quantum bit to be operated is subjected to target operation to obtain an actual superposition quantum state matrix, multiplying the actual superposition quantum state matrix by the crosstalk compensation matrix to obtain a calculated result matrix after crosstalk compensation.
In a third aspect, an embodiment of the present application provides a compensation apparatus for qubit driven crosstalk, the apparatus including:
the driving crosstalk intensity acquisition module is used for acquiring driving crosstalk intensity between a target quantum bit and a neighboring quantum bit, wherein the target quantum bit is a driven quantum bit;
The actual operation matrix determining module is used for determining an actual operation matrix of the target quantum bit according to the driving crosstalk intensity;
And the crosstalk compensation matrix determining module is used for determining a crosstalk compensation matrix between the target quantum bit and the adjacent quantum bit according to the target superposition quantum state matrix corresponding to the target quantum bit and the actual operation matrix.
In a fourth aspect, an embodiment of the present application provides a qubit compensation apparatus, the apparatus including:
The quantum bit acquisition module is used for acquiring quantum bits to be operated;
The query module is configured to query a compensation matrix database for whether a crosstalk compensation matrix corresponding to the to-be-operated qubit exists, where the compensation matrix database stores a crosstalk compensation matrix between any one qubit and a neighboring qubit of the qubit, where the crosstalk compensation matrix between any one qubit and the neighboring qubit of the qubit is calculated according to the compensation method for the qubit driving crosstalk according to the first aspect of the embodiment;
The compensation module is used for existence of a crosstalk compensation matrix corresponding to the quantum bit to be operated in the compensation matrix database, and multiplying the actual superposition quantum state matrix by the crosstalk compensation matrix after target operation of the quantum bit to be operated to obtain an actual superposition quantum state matrix, so as to obtain a calculated result matrix after crosstalk compensation.
In a fifth aspect, embodiments of the present application provide a quantum computer, comprising: at least one processor, and a memory storing a computer program executable on the processor, wherein the processor, when executing the program, performs the method of compensating for qubit drive crosstalk as described in the first aspect of the embodiments, or the method of compensating for qubits as described in the second aspect of the embodiments.
In a sixth aspect, embodiments of the present application provide a non-volatile readable storage medium storing a computer program, wherein the computer program when executed by a processor performs the method of compensating for qubit drive crosstalk as described in the first aspect of the embodiments or the method of qubit compensation as described in the second aspect of the embodiments.
The beneficial effects are that:
Acquiring driving crosstalk intensity between a target quantum bit and a neighbor quantum bit, wherein the target quantum bit is a driven quantum bit; determining an actual operation matrix of the target quantum bit according to the driving crosstalk intensity; and determining a crosstalk compensation matrix between the target quantum bit and the adjacent quantum bit according to the target superposition quantum state matrix corresponding to the target quantum bit and the actual operation matrix.
By calculating the driving crosstalk intensity between the target quantum bit and the adjacent quantum bit, then determining the actual operation matrix of the target quantum bit, according to the target superposition quantum state matrix and the actual operation matrix corresponding to the target quantum bit, the crosstalk compensation matrix between the target quantum bit and the adjacent quantum bit can be calculated, and driving crosstalk compensation can be performed when the target quantum bit is driven after the crosstalk compensation matrix is obtained, so that driving crosstalk is restrained, and quantum logic operation fidelity is improved.
Drawings
In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below.
Fig. 1 is a flowchart illustrating steps of a method for compensating for qubit driving crosstalk according to an embodiment of the present application;
FIG. 2 illustrates an initial quantum state preparation schematic provided by an embodiment of the present application;
FIG. 3 is a flow chart illustrating steps of a method for qubit compensation according to an embodiment of the present application;
FIG. 4 is a functional block diagram of a compensation device for qubit drive crosstalk according to an embodiment of the present application;
fig. 5 shows a functional block diagram of a qubit compensation device according to an embodiment of the present application.
Detailed Description
The technical solutions in the embodiments of the present application will be described below with reference to the accompanying drawings in the embodiments of the present application.
For the purpose of making the objects, technical solutions and advantages of the embodiments of the present application more apparent, the following detailed description of the embodiments of the present application will be given with reference to the accompanying drawings. However, those of ordinary skill in the art will understand that in various embodiments of the present application, numerous technical details have been set forth in order to provide a better understanding of the present application. The claimed application may be practiced without these specific details and with various changes and modifications based on the following embodiments. The following embodiments are divided for convenience of description, and should not be construed as limiting the specific implementation of the present application, and the embodiments can be mutually combined and referred to without contradiction.
Under the condition that the computing power of the traditional chip is limited, quantum computing is one of the popular research directions for continuously improving the computing power.
The potential computational power advantage of quantum computing arises from its inherent computational parallelism, in classical computing a single bit can only be at 0 or 1, but in quantum computing a single qubit can be in the superposition of |0>, |1>, or |0> and |1>, namely:
Wherein, | > is a Dirac symbol for representing a certain quantum state; when the qubit is in the superposition state, the qubit can be regarded as being in two states of |0> and |1>, all operations on the qubit are equivalent to simultaneous operations on |0> and |1>, a and b are complex numbers, a 2 represents the probability that the result obtained by reading the qubit in the superposition state is |0>, b 2 represents the probability that the result obtained by reading the qubit in the superposition state is |1>, and a and b satisfy the normalization condition a 2+b2 =1.
Also, because a single qubit can be in a superposition state formed by two ground states, an n-bit qubit can be in a superposition state formed by 2 n calculation ground states, and an operation on the superposition state can be regarded as an operation on all the ground states forming the superposition state simultaneously, that is, quantum calculation has inherent parallelism and potential computational power advantages over classical calculation.
However, there is a problem of driving crosstalk between adjacent qubits, and the crosstalk between nearest neighbor qubits is derived from leakage of a microwave signal driven by a single bit to a neighboring qubit on a quantum chip and transverse field coupling between two neighboring qubits, so that the most commonly studied inter-bit crosstalk mode is a phase error caused by direct current crosstalk of a magnetic flux signal at present, and less research is conducted on degradation of logic operation fidelity caused by driving crosstalk between qubits.
Therefore, the present embodiment provides a compensation method for driving crosstalk of a qubit, which can calculate the driving crosstalk intensity between the qubits, determine the driving crosstalk compensation between the qubits, and reduce the adverse effect on the logic operation fidelity of the qubit caused by the unwanted state change of the neighboring bits due to the driving crosstalk.
Referring to fig. 1, a step flow chart of a method for compensating for qubit driving crosstalk according to an embodiment of the present application is shown, where the method may include the following steps:
S101: and acquiring the driving crosstalk intensity between the target quantum bit and the adjacent quantum bit, wherein the target quantum bit is the driving quantum bit.
When driving the target qubit, because of leakage of a microwave signal driven by a single bit to a neighboring qubit on the quantum chip or transverse field coupling between two neighboring qubits, driving crosstalk exists between the target qubit and the neighboring qubit, and unwanted state changes occur in the neighboring qubit.
In a possible implementation, when obtaining the driving crosstalk intensity between the target qubit and the neighboring qubit, the method may include the following steps:
a1: initializing quantum states of the target quantum bit and the neighbor quantum bit to obtain different initialized quantum states.
Illustratively, the target qubit is denoted as q 0 and the neighboring qubit is denoted as q 1; the quantum state arrangement of the target qubit and the neighbor qubit is |q 1q0 >.
The column matrix corresponding to the superposition quantum state of the target quantum bit and the adjacent quantum bit is:
Where the coefficient a, b, c, d is referred to as a probability amplitude, and the square of the probability amplitude represents the probability of reading each basis vector, for example, is the probability of reading |00>, is the probability of reading |01>, is the probability of reading |10>, and is the probability of reading |11 >.
For quantum state operation, which is equivalent to changing one quantum state to another, i.e. changing the coefficient a, b, c, d, the new quantum state obtained after any quantum state operation is assumed to be:
Wherein e, f, g, h is the probability width of the corresponding basis vector read in the new quantum state, and the square of the probability width is the probability of the corresponding basis vector read.
Referring to fig. 2, an initial quantum state preparation schematic diagram provided in this embodiment is shown, and the quantum states of the target quantum bit and the neighboring quantum bit are initialized to obtain initialized different quantum states, where the initialized different quantum states include: initial quantum state |00>, initial quantum state |01>, initial quantum state |10>, and initial quantum state |11>.
A2: and respectively acting the Brix gates of the target times for the target quantum bits in the initialized different quantum states to obtain the respective corresponding actual quantum state acting results of the different quantum states.
The brix gate corresponds to a classical NOT gate, and the brix gate acting on the target qubit q 0 is, in an ideal state:
However, in the process of actual logic operation, since there may be driving crosstalk between the target qubit and the neighboring qubit, the actual operation matrix corresponding to the brix gate when there is driving crosstalk may not be consistent with the brix gate, and it is assumed that the brix gate corresponds to the actual operation matrix P when there is driving crosstalk.
And obtaining respective corresponding actual quantum state action results of different quantum states, namely, under the initial quantum state |00>, the initial quantum state |01>, the initial quantum state |10> and the initial quantum state |11>, respectively acting on the Brix gates of the target number of times on the different initialized quantum states, counting and calculating crosstalk probability of change of the adjacent quantum bits in the respective corresponding actual quantum state action results of the different quantum states in the target number of times, and counting and calculating generation probability of the target quantum states in the respective corresponding actual quantum state action results of the different quantum states in the target number of times, wherein the target quantum states refer to quantum states which should be generated when the target quantum bit q 0 acts on the Brix gates of the ideal state.
The target number of times can be set in a self-defined manner according to the actual application requirements, and the embodiment is not limited.
Specifically, the Brix gate of the target times is acted on the target quantum bit in the initial quantum state |00>, a corresponding actual quantum state acting result is obtained, the probability of obtaining the quantum state |01> and the probability of obtaining the quantum state |11> are determined, and the probability of obtaining the quantum state |01> is taken as the first generation probability of the target quantum state in the initial quantum state |00 >; and taking the probability of the obtained quantum state |11> as a first crosstalk probability of the adjacent quantum bit in the initial quantum state |00 >.
When a brix gate is applied to the target qubit q 0 in the initial qustate |00>, the target qustate should be |01>, i.e., only the state of the target qubit q 0 changes, while the state of the neighboring qubit q 1 remains unchanged, i.e., should be:
Wherein X is Brix gate.
However, since there may be neighbor driving crosstalk, the brix gate acting on the target qubit q 0 will act on the neighbor qubit q 1, that is, in addition to obtaining the |01> state, it may also obtain the |11> state, that is, when there is driving crosstalk, the actual quantum state acting result obtained by the action of the actual operation matrix P corresponding to the brix gate is:
Wherein is the probability of quantum state |01>,/( is the probability of quantum state |11>,/( is the probability of obtaining quantum state |01>, and/() is the probability of obtaining quantum state |11>, i.e. the probability of obtaining quantum state |01 >/> is the first generation probability of the target quantum state in the initial quantum state |00 >; and taking the probability of the obtained quantum state |11> as a first crosstalk probability of the adjacent quantum bit in the initial quantum state |00 >.
And applying the Brix gate of the target times to the target quantum bit in the initial quantum state |01>, obtaining a corresponding actual quantum state action result, determining the probability of obtaining the quantum state |00> and the probability of obtaining the quantum state |10>, taking the probability of obtaining the quantum state |00> as the second generation probability of the target quantum state in the initial quantum state |01>, and taking the probability of obtaining the quantum state |10> as the second crosstalk probability of changing the adjacent quantum bit in the initial quantum state |01 >.
When a brix gate is applied to the target qubit q 0 in the initial qustate |01>, the target qustate should be |00>, i.e., only the state of the target qubit q 0 changes, while the state of the neighboring qubit q 1 remains unchanged, i.e., should be:
However, since there may be neighbor driving crosstalk, the brix gate acting on the target qubit q 0 will act on the neighbor qubit q 1, i.e. besides obtaining the |00> state, there may be obtained the |10> state, i.e. when there is driving crosstalk, the actual quantum state acting result obtained by the action of the actual operation matrix P corresponding to the brix gate is:
Wherein is the probability of quantum state |00>,/( is the probability of quantum state |10>,/( is the probability of obtaining quantum state |00>,/( is the probability of obtaining quantum state |10>, i.e. the probability/> of obtaining quantum state |00> is the second generation probability of the target quantum state in the initial quantum state |01>, and the probability of obtaining quantum state |10> is the second crosstalk probability of the adjacent quantum bit in the initial quantum state |01 >.
And applying the Brix gate of the target times to the target quantum bit in the initial quantum state |10>, obtaining a corresponding actual quantum state action result, determining the probability of obtaining the quantum state |11> and the probability of obtaining the quantum state |01>, taking the probability of obtaining the quantum state |11> as the third generation probability of the target quantum state in the initial quantum state |10>, and taking the probability of obtaining the quantum state |01> as the third crosstalk probability of changing the adjacent quantum bit in the initial quantum state |10 >.
When a brix gate is applied to the target qubit q 0 in the initial qustate |10>, the target qustate should be |11>, i.e., only the state of the target qubit q 0 changes, while the state of the neighboring qubit q 1 remains unchanged, i.e., should be:
However, since there may be neighbor driving crosstalk, the brix gate acting on the target qubit q 0 will act on the neighbor qubit q 1, that is, in addition to obtaining the |11> state, it may also obtain the |01> state, that is, when there is driving crosstalk, the actual quantum state acting result obtained by the action of the actual operation matrix P corresponding to the brix gate is:
Wherein is a probability width of a quantum state |11>,/( is a probability width of a quantum state |01>,/( is a probability of a quantum state |11>,/( is a probability of a quantum state |01>, i.e., a probability of a quantum state |11> is obtained/> is used as a third generation probability of the target quantum state in the initial quantum state |10>, and a probability of a quantum state |01> is used as a third crosstalk probability of a neighboring quantum bit in the initial quantum state |10 >.
And applying the Brix gate of the target times to the target quantum bit in the initial quantum state |11>, obtaining a corresponding actual quantum state action result, determining the probability of obtaining the quantum state |10> and the probability of obtaining the quantum state |00>, taking the probability of obtaining the quantum state |10> as the fourth generation probability of the target quantum state in the initial quantum state |11>, and taking the probability of obtaining the quantum state |00> as the fourth crosstalk probability of changing the adjacent quantum bit in the initial quantum state |11 >.
When a brix gate is applied to the target qubit q 0 in the initial qustate |11>, the target qustate should be |10>, i.e., only the state of the target qubit q 0 changes, while the state of the neighboring qubit q 1 remains unchanged, i.e., should be:
However, since there may be neighbor driving crosstalk, the brix gate acting on the target qubit q 0 will act on the neighbor qubit q 1, i.e. besides obtaining the |10> state, there is also a possibility that the |00> state is obtained, i.e. when there is driving crosstalk, the actual quantum state acting result obtained by the action of the actual operation matrix P corresponding to the brix gate is:
Wherein is the probability of quantum state |10>,/( is the probability of quantum state |00>,/( is the probability of obtaining quantum state |10>,/( is the probability of obtaining quantum state |00>, i.e. the probability/> of obtaining quantum state |10> is the fourth generation probability of the target quantum state in the initial quantum state |11>, and the probability of obtaining quantum state |00> is the fourth crosstalk probability of the neighboring quantum bit in the initial quantum state |11 >.
A3: and obtaining the driving crosstalk intensity between the target quantum bit and the adjacent quantum bit according to the crosstalk probability of the adjacent quantum bit in the actual quantum state action result corresponding to each different quantum state.
If the driving crosstalk exists between the target qubit q 0 and the neighboring qubit q 1, all probabilities obtained in the above action process are generally the same value, but a certain error exists in the obtained probabilities in consideration of possible system errors, so in this embodiment, the crosstalk probabilities in 4 different quantum states are averaged to obtain the driving crosstalk intensity between the target qubit and the neighboring qubit.
That is, the first crosstalk probability , the second crosstalk probability/> , the third crosstalk probability/> , and the fourth crosstalk probability/> are averaged as follows:
the average is taken as the driving crosstalk strength between the target qubit and the neighboring qubit.
In addition, after the brix gate of the target number of times acts on the target qubit in the initialized different quantum states respectively to obtain the respective corresponding actual quantum state acting results of the different quantum states, the method further includes:
And determining the normal generation probability of the Brix gate according to the generation probability of the target quantum state in the actual quantum state action results corresponding to the different quantum states.
Specifically, the average of the first generation probability , the second generation probability/> , the third generation probability , and the fourth generation probability/> is calculated as follows:
The average is taken as the normal generation probability of the Brix gate, namely the probability of normally realizing the Brix gate function.
S102: and determining an actual operation matrix of the target quantum bit according to the driving crosstalk intensity.
The expression of the actual operation matrix P for determining the target qubit can be obtained by calculating the normal generation probability of the brix gate and the driving crosstalk intensity, which are obtained by averaging, and is as follows:
Wherein is the normal generation probability of the brix gate, and/() is the driving crosstalk intensity.
If there is no drive crosstalk between the target qubit q 0 and the neighboring qubit q 1, there is and/> , i.e., the actual operating matrix P is equal to the brix gate.
S103: and determining a crosstalk compensation matrix between the target quantum bit and the adjacent quantum bit according to the target superposition quantum state matrix corresponding to the target quantum bit and the actual operation matrix.
After determining the drive crosstalk between the target qubit q 0 and the neighboring qubit q 1, the adverse effects of the drive crosstalk can be compensated for to recover the ideal state.
Specifically, in an ideal state, the process of obtaining the target superposition quantum state matrix by applying the brix gate to the target quantum bit q 0 to the general superposition state is as follows:
Wherein is the target stacked quantum state matrix.
However, because of the driving crosstalk between the qubits, the actual superposition quantum state matrix is first determined according to the actual operation matrix P corresponding to the brix gate under the driving crosstalk.
Specifically, when the actual operation matrix P corresponding to the berlite X gate acts on the general superposition state, the process of obtaining the actual superposition quantum state matrix is as follows:
Wherein P is the actual operation matrix corresponding to the brix gate under driving crosstalk, and is the actual superposition quantum state matrix.
And then, according to the actual superposition quantum state matrix and the target superposition quantum state matrix, calculating to obtain a crosstalk compensation matrix between the target quantum bit and the adjacent quantum bit.
In particular, assuming that A is the crosstalk compensation matrix between the target qubit and the neighboring qubit,
The crosstalk compensation matrix a can be calculated as:
Wherein a is a crosstalk compensation matrix between the target qubit and the neighboring qubit, and is the actual superposition quantum state matrix.
In a possible implementation manner, after the crosstalk compensation matrix between the target qubit and the neighboring qubit is determined, the crosstalk compensation matrix between the target qubit and the neighboring qubit may be stored in a compensation matrix database, so that in an application, the crosstalk compensation matrix between the target qubit and the neighboring qubit may be obtained directly, and a matrix multiplication of the compensation matrix a may be performed on a quantum state read after the application of the brix gate, so as to obtain an actual calculation result after the application of the brix gate, and may offset an adverse effect caused by driving crosstalk between bits.
In addition, since the driving crosstalk is not constant, in order to ensure the accuracy of the crosstalk compensation matrix between the target qubit and the neighboring qubit, the crosstalk compensation matrix between the target qubit and the neighboring qubit stored in the compensation matrix database may be updated at preset time intervals, that is, the crosstalk compensation matrix between the target qubit and the neighboring qubit is recalculated by using the above-mentioned compensation method for the driving crosstalk of the qubit.
Referring to fig. 3, a flowchart of steps of a method for quantum bit compensation according to an embodiment of the present application is shown, where the method includes the following steps:
s201: and acquiring the quantum bit to be operated.
The qubit to be operated is a qubit that needs to be logically operated or driven.
S202: and inquiring whether a crosstalk compensation matrix corresponding to the quantum bit to be operated exists in a compensation matrix database, wherein the crosstalk compensation matrix between any quantum bit and the adjacent quantum bit of the quantum bit is stored in the compensation matrix database.
The crosstalk compensation matrix between any one qubit and the adjacent qubit of the qubit is calculated according to the compensation method of the qubit driving crosstalk described in the embodiment.
S203: and if the crosstalk compensation matrix corresponding to the quantum bit to be operated exists in the compensation matrix database, after the quantum bit to be operated is subjected to target operation to obtain an actual superposition quantum state matrix, multiplying the actual superposition quantum state matrix by the crosstalk compensation matrix to obtain a calculated result matrix after crosstalk compensation.
Specifically, when the brix gate is applied to the quantum bit to be operated, because of the existence of the driving crosstalk between bits, the actual operation matrix corresponding to the brix gate is P, in order to offset the adverse effect caused by the driving crosstalk between bits, the actual superposition quantum state matrix obtained after the brix gate is applied can be multiplied by the crosstalk compensation matrix, so as to obtain the calculated result matrix after the crosstalk compensation.
In this embodiment, since drive crosstalk easily exists between adjacent superconducting qubits, a state change of a neighboring qubit may be caused when a drive quantum logic gate (i.e., a brix gate) is applied to one of the qubits, so an experimental method for determining the drive crosstalk strength between two adjacent qubits is provided first, and then, based on the effect result of the quantum logic gate actually implemented under the drive crosstalk on two general qubits, a crosstalk compensation matrix between two adjacent qubits is deduced, and by multiplying the compensation matrix with the effect of the actually acting quantum logic gate, the effect result of the drive quantum logic gate on any general qubit in an ideal state can be obtained, and adverse effects caused by the drive crosstalk are compensated, thereby improving the operational fidelity of the quantum logic gate.
Referring to fig. 4, there is shown a functional block diagram of a compensation apparatus for qubit drive crosstalk provided in this embodiment, the apparatus includes:
a driving crosstalk intensity acquisition module 101, configured to acquire driving crosstalk intensity between a target qubit and a neighboring qubit, where the target qubit is a driven qubit;
The actual operation matrix determining module 102 is configured to determine an actual operation matrix of the target qubit according to the driving crosstalk intensity;
and the crosstalk compensation matrix determining module 103 is configured to determine a crosstalk compensation matrix between the target qubit and the neighboring qubit according to the target superposition quantum state matrix corresponding to the target qubit and the actual operation matrix.
Optionally, the driving crosstalk intensity acquisition module includes:
the initialization unit is used for initializing the quantum states of the target quantum bit and the adjacent quantum bit to obtain different initialized quantum states;
The actual quantum state action result generation unit is used for respectively acting the Brix gates of the target times for the target quantum bits in the initialized different quantum states to obtain respective corresponding actual quantum state action results of the different quantum states;
And the driving crosstalk intensity determining unit is used for obtaining the driving crosstalk intensity between the target quantum bit and the adjacent quantum bit according to the crosstalk probability of the adjacent quantum bit in the actual quantum state action result corresponding to each different quantum state.
Optionally, the apparatus further comprises:
And the normal generation probability determining module is used for determining the normal generation probability of the Brix gate according to the generation probability of the target quantum state in the actual quantum state action results corresponding to the different quantum states.
Optionally, the initializing unit includes:
An initialization subunit, configured to mark the target qubit as q 0, and the neighboring qubit as q 1; the quantum state arrangement of the target quantum bit and the adjacent quantum bit is |q 1q0 >; initializing quantum states of the target quantum bit and the neighbor quantum bit to obtain initialized different quantum states, wherein the initialized different quantum states comprise: initial quantum state |00>, initial quantum state |01>, initial quantum state |10>, and initial quantum state |11>.
Optionally, the actual quantum state action result generating unit includes:
A first actual quantum state action result generation subunit, configured to act, on the target qubit, on the brix gate of the target number of times in the initial quantum state |00>, obtain a corresponding actual quantum state action result, determine a probability of obtaining a quantum state |01> and a probability of obtaining a quantum state |11>, and use the probability of obtaining a quantum state |01> as a first generation probability of the target quantum state in the initial quantum state |00 >; taking the probability of the obtained quantum state |11> as a first crosstalk probability of the adjacent quantum bit in the initial quantum state |00 >;
A second actual quantum state action result generation subunit, configured to act, on the target qubit in the initial quantum state |01>, on a brix gate of the target number of times, to obtain a corresponding actual quantum state action result, determine a probability of obtaining a quantum state |00> and a probability of obtaining a quantum state |10>, use the probability of obtaining the quantum state |00> as a second generation probability of the target quantum state in the initial quantum state |01>, and use the probability of obtaining the quantum state |10> as a second crosstalk probability of the neighboring qubit in the initial quantum state |01 >;
a third actual quantum state action result generation subunit, configured to act, on the target quantum bit in the initial quantum state |10>, the brix gate of the target number of times to obtain a corresponding actual quantum state action result, determine a probability of obtaining a quantum state |11> and a probability of obtaining a quantum state |01>, use the probability of obtaining the quantum state |11> as a third generation probability of the target quantum state in the initial quantum state |10>, and use the probability of obtaining the quantum state |01> as a third crosstalk probability of the neighboring quantum bit in the initial quantum state |10 >;
A fourth actual quantum state action result generation subunit, configured to act, on the target quantum bit in the initial quantum state |11>, the brix gate of the target number of times to obtain a corresponding actual quantum state action result, determine a probability of obtaining a quantum state |10> and a probability of obtaining a quantum state |00>, use the probability of obtaining the quantum state |10> as a fourth generation probability of the target quantum state in the initial quantum state |11>, and use the probability of obtaining the quantum state |00> as a fourth crosstalk probability of the neighboring quantum bit in the initial quantum state |11 >.
Optionally, the driving crosstalk intensity determining unit includes:
And the driving crosstalk intensity determining subunit is used for averaging the first crosstalk probability, the second crosstalk probability, the third crosstalk probability and the fourth crosstalk probability, and taking the average value as the driving crosstalk intensity between the target quantum bit and the adjacent quantum bit.
Optionally, the normal generation probability determining module includes:
And the normal generation probability determining unit is used for calculating an average value of the first generation probability, the second generation probability, the third generation probability and the fourth generation probability, and taking the average value as the normal generation probability of the Brix gate.
Optionally, the actual operation matrix determining module includes:
And the actual operation matrix determining unit is used for determining the actual operation matrix of the target quantum bit according to the normal generation probability of the Brix gate and the driving crosstalk intensity.
Optionally, the crosstalk compensation matrix determining module includes:
the first unit is used for determining an actual superposition quantum state matrix according to the actual operation matrix corresponding to the Brix gate under driving crosstalk;
And the second unit is used for calculating and obtaining a crosstalk compensation matrix between the target quantum bit and the adjacent quantum bit according to the actual superposition quantum state matrix and the target superposition quantum state matrix.
Optionally, the apparatus further comprises:
And the storage module is used for storing the crosstalk compensation matrix between the target qubit and the adjacent qubit in a compensation matrix database.
Optionally, the apparatus further comprises:
And the updating module is used for updating the crosstalk compensation matrix between the target quantum bit and the adjacent quantum bit stored in the compensation matrix database at preset time intervals.
Referring to fig. 5, there is shown a functional block diagram of a qubit compensation device according to the present embodiment, the device includes:
a qubit obtaining module 201 to be operated, configured to obtain a qubit to be operated;
A query module 202, configured to query a compensation matrix database for whether a crosstalk compensation matrix corresponding to the to-be-operated qubit exists, where the compensation matrix database stores a crosstalk compensation matrix between any one qubit and a neighboring qubit of the qubit, where the crosstalk compensation matrix between any one qubit and the neighboring qubit of the qubit is calculated according to a compensation method of a qubit driving crosstalk described in the embodiment;
And the compensation module 203 is configured to store a crosstalk compensation matrix corresponding to the to-be-operated quantum bit in the compensation matrix database, and multiply the actual superposition quantum state matrix with the crosstalk compensation matrix after performing a target operation on the to-be-operated quantum bit to obtain a calculated result matrix after crosstalk compensation.
The embodiment of the application also provides a quantum computer, which comprises: at least one processor, and a memory storing a computer program executable on the processor, wherein the processor performs a method of compensating for qubit drive crosstalk as described in the embodiments or a method of qubit compensation as described in the embodiments when the program is executed.
The embodiments of the present application also provide a non-volatile readable storage medium storing a computer program, wherein the computer program when executed by a processor performs the method of compensating for qubit drive crosstalk as described in the embodiments, or the method of qubit compensation as described in the embodiments.
In this specification, each embodiment is described in a progressive manner, and each embodiment is mainly described by differences from other embodiments, and identical and similar parts between the embodiments are all enough to be referred to each other.
It will be apparent to those skilled in the art that embodiments of the present application may be provided as a method, apparatus, or computer program product. Accordingly, embodiments of the present application may take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, embodiments of the application may take the form of a computer program product on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) having computer-usable program code embodied therein.
Embodiments of the present application are described with reference to flowchart illustrations and/or block diagrams of methods, terminal devices (systems), and computer program products according to embodiments of the application. It will be understood that each flow and/or block of the flowchart illustrations and/or block diagrams, and combinations of flows and/or blocks in the flowchart illustrations and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing terminal device to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing terminal device, create means for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.
These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means which implement the function specified in the flowchart flow or flows and/or block diagram block or blocks.
These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.
While preferred embodiments of the present application have been described, additional variations and modifications in those embodiments may occur to those skilled in the art once they learn of the basic inventive concepts. It is therefore intended that the following claims be interpreted as including the preferred embodiment and all such alterations and modifications as fall within the scope of the embodiments of the application.
Finally, it is further noted that relational terms such as first and second, and the like are used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Moreover, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or terminal that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or terminal. Without further limitation, an element defined by the phrase "comprising one … …" does not exclude the presence of other like elements in a process, method, article, or terminal device that comprises the element.
The principles and embodiments of the present application have been described herein with reference to specific examples, the description of which is intended only to assist in understanding the methods of the present application and the core ideas thereof; meanwhile, as those skilled in the art will have variations in the specific embodiments and application scope in accordance with the ideas of the present application, the present description should not be construed as limiting the present application in view of the above.
Claims (23)
1. A method of compensating for qubit-driven crosstalk, the method comprising:
acquiring driving crosstalk intensity between a target quantum bit and a neighbor quantum bit, wherein the target quantum bit is a driven quantum bit;
Determining an actual operation matrix of the target quantum bit according to the driving crosstalk intensity;
and determining a crosstalk compensation matrix between the target quantum bit and the adjacent quantum bit according to the target superposition quantum state matrix corresponding to the target quantum bit and the actual operation matrix.
2. The method of claim 1, wherein obtaining the drive crosstalk strength between the target qubit and the neighboring qubit comprises:
Initializing quantum states of the target quantum bit and the neighbor quantum bit to obtain initialized different quantum states;
Respectively acting the Brix gates of the target times for the target quantum bits in the initialized different quantum states to obtain respective corresponding actual quantum state acting results of the different quantum states;
And obtaining the driving crosstalk intensity between the target quantum bit and the adjacent quantum bit according to the crosstalk probability of the adjacent quantum bit in the actual quantum state action result corresponding to each different quantum state.
3. The method according to claim 2, wherein, in the initialized different quantum states, respectively, the brix gate of the target number of times is acted on the target quantum bit, and after obtaining the respective corresponding actual quantum state acting results of the different quantum states, the method further comprises:
And determining the normal generation probability of the Brix gate according to the generation probability of the target quantum state in the actual quantum state action results corresponding to the different quantum states.
4. A method according to claim 3, wherein initializing the quantum states of the target qubit and the neighboring qubit to obtain different initialized quantum states comprises:
Designating the target qubit as q 0 and the neighboring qubit as q 1;
The quantum state arrangement of the target quantum bit and the adjacent quantum bit is |q 1q0 >;
Initializing quantum states of the target quantum bit and the neighbor quantum bit to obtain initialized different quantum states, wherein the initialized different quantum states comprise: initial quantum state |00>, initial quantum state |01>, initial quantum state |10>, and initial quantum state |11>.
5. The method of claim 4, wherein the act of acting the brix gate for the target qubit a target number of times in the initialized different quantum states to obtain respective corresponding actual quantum state acting results for the different quantum states includes:
The Brix gate of the target times acts on the target quantum bit in the initial quantum state |00>, a corresponding actual quantum state acting result is obtained, the probability of obtaining the quantum state |01> and the probability of obtaining the quantum state |11> are determined, and the probability of obtaining the quantum state |01> is taken as the first generation probability of the target quantum state in the initial quantum state |00 >; taking the probability of the obtained quantum state |11> as a first crosstalk probability of the adjacent quantum bit in the initial quantum state |00 >;
The Brix gate of the target times acts on the target quantum bit in the initial quantum state |01>, a corresponding actual quantum state acting result is obtained, the probability of obtaining the quantum state |00> and the probability of obtaining the quantum state |10> are determined, the probability of obtaining the quantum state |00> is used as the second generation probability of the target quantum state in the initial quantum state |01>, and the probability of obtaining the quantum state |10> is used as the second crosstalk probability of the adjacent quantum bit in the initial quantum state |01 >;
The Brix gate of the target times acts on the target quantum bit in the initial quantum state |10>, a corresponding actual quantum state acting result is obtained, the probability of obtaining a quantum state |11> and the probability of obtaining a quantum state |01> are determined, the probability of obtaining the quantum state |11> is used as the third generation probability of the target quantum state in the initial quantum state |10>, and the probability of obtaining the quantum state |01> is used as the third crosstalk probability of the adjacent quantum bit in the initial quantum state |10 >;
And applying the Brix gate of the target times to the target quantum bit in the initial quantum state |11>, obtaining a corresponding actual quantum state action result, determining the probability of obtaining the quantum state |10> and the probability of obtaining the quantum state |00>, taking the probability of obtaining the quantum state |10> as the fourth generation probability of the target quantum state in the initial quantum state |11>, and taking the probability of obtaining the quantum state |00> as the fourth crosstalk probability of changing the adjacent quantum bit in the initial quantum state |11 >.
6. The method according to claim 5, wherein obtaining the driving crosstalk intensity between the target qubit and the neighboring qubit according to the crosstalk probability of the neighboring qubit being changed in the actual quantum state action result corresponding to each of the different quantum states comprises:
And averaging the first crosstalk probability, the second crosstalk probability, the third crosstalk probability and the fourth crosstalk probability, and taking the average value as the driving crosstalk intensity between the target quantum bit and the adjacent quantum bit.
7. The method of claim 5, wherein determining the normal generation probability of the brix gate based on the generation probability of the target quantum state in the actual quantum state effect result corresponding to each of the different quantum states comprises:
And calculating the average value of the first generation probability, the second generation probability, the third generation probability and the fourth generation probability, and taking the average value as the normal generation probability of the Brix gate.
8. The method of claim 5, wherein the acting of the brix gate for the target number of times on the target qubit in the initial quantum state |00> yields the corresponding actual quantum state effect result as:
Wherein P is an actual operation matrix corresponding to the Brix gate when driving crosstalk exists; Is the probability of quantum state |01>, is the probability of quantum state |11>, is the probability of quantum state |01>, and is the probability of quantum state |11 >.
9. The method of claim 5, wherein the acting of the brix gate for the target number of times on the target qubit in the initial quantum state |01> yields the corresponding actual quantum state effect result as:
Wherein P is an actual operation matrix corresponding to the Brix gate when driving crosstalk exists; Is the probability of quantum state |00>, is the probability of quantum state |10>, is the probability of quantum state |00>, and is the probability of quantum state |10 >.
10. The method of claim 5, wherein the acting of the brix gate for the target number of times on the target qubit in the initial quantum state |10> yields the corresponding actual quantum state effect result as:
Wherein P is an actual operation matrix corresponding to the Brix gate when driving crosstalk exists; Is the probability of quantum state |11>, is the probability of quantum state |01>, is the probability of quantum state |11>, and is the probability of quantum state |01 >.
11. The method of claim 5, wherein the acting of the brix gate for the target number of times on the target qubit in the initial quantum state |11> yields the corresponding actual quantum state effect result as:
Wherein P is an actual operation matrix corresponding to the Brix gate when driving crosstalk exists; Is the probability of quantum state |10>, is the probability of quantum state |00>, is the probability of quantum state |10>, and is the probability of quantum state |00 >.
12. A method according to claim 3, wherein determining the actual operating matrix of the target qubit based on the drive crosstalk intensity comprises:
And determining an actual operation matrix of the target qubit according to the normal generation probability of the Brix gate and the driving crosstalk intensity.
13. The method of claim 12, wherein the actual operating matrix is:
wherein P is an actual operation matrix corresponding to the Brix gate when driving crosstalk exists; For the normal generation probability of the brix gate,/> is the drive crosstalk intensity.
14. The method of claim 13, wherein determining a crosstalk compensation matrix between the target qubit and the neighboring qubit based on the target stacked qustate matrix and the actual operation matrix corresponding to the target qubit comprises:
Determining an actual superposition quantum state matrix according to the actual operation matrix corresponding to the Brix gate under driving crosstalk;
and calculating to obtain a crosstalk compensation matrix between the target quantum bit and the adjacent quantum bit according to the actual superposition quantum state matrix and the target superposition quantum state matrix.
15. The method of claim 14, wherein the formula for determining the actual superimposed quantum state matrix based on the actual operating matrix corresponding to the brix gate under driving crosstalk is:
Wherein P is the actual operation matrix corresponding to the brix gate under driving crosstalk, and is the actual superposition quantum state matrix.
16. The method of claim 15, wherein the formula for calculating the crosstalk compensation matrix between the target qubit and the neighboring qubit based on the actual stacked quantum state matrix and the target stacked quantum state matrix is:
the crosstalk compensation matrix A is calculated as follows:
Wherein a is a crosstalk compensation matrix between the target qubit and the neighboring qubit, is the actual stacked quantum state matrix, and/> is the target stacked quantum state matrix.
17. The method of claim 1, wherein after determining the crosstalk compensation matrix between the target qubit and the neighboring qubit according to the target stacked qustate matrix and the actual operation matrix corresponding to the target qubit, the method further comprises:
and storing a crosstalk compensation matrix between the target qubit and the neighboring qubit in a compensation matrix database.
18. The method of claim 17, wherein after storing the crosstalk compensation matrix between the target qubit and the neighboring qubit in a compensation matrix database, the method further comprises:
And updating a crosstalk compensation matrix between the target qubit and the adjacent qubit stored in the compensation matrix database at preset time intervals.
19. A method of qubit compensation, the method comprising:
Acquiring quantum bits to be operated;
Inquiring whether a crosstalk compensation matrix corresponding to the quantum bit to be operated exists in a compensation matrix database, wherein the crosstalk compensation matrix between any quantum bit and a quantum bit adjacent to the quantum bit is stored in the compensation matrix database, and the crosstalk compensation matrix between any quantum bit and a quantum bit adjacent to the quantum bit is calculated according to the quantum bit driving crosstalk compensation method according to any one of claims 1-18;
And if the crosstalk compensation matrix corresponding to the quantum bit to be operated exists in the compensation matrix database, after the quantum bit to be operated is subjected to target operation to obtain an actual superposition quantum state matrix, multiplying the actual superposition quantum state matrix by the crosstalk compensation matrix to obtain a calculated result matrix after crosstalk compensation.
20. A compensation device for qubit driven crosstalk, the device comprising:
the driving crosstalk intensity acquisition module is used for acquiring driving crosstalk intensity between a target quantum bit and a neighboring quantum bit, wherein the target quantum bit is a driven quantum bit;
The actual operation matrix determining module is used for determining an actual operation matrix of the target quantum bit according to the driving crosstalk intensity;
And the crosstalk compensation matrix determining module is used for determining a crosstalk compensation matrix between the target quantum bit and the adjacent quantum bit according to the target superposition quantum state matrix corresponding to the target quantum bit and the actual operation matrix.
21. A qubit compensation device, the device comprising:
The quantum bit acquisition module is used for acquiring quantum bits to be operated;
A query module, configured to query a compensation matrix database for whether a crosstalk compensation matrix corresponding to the qubit to be operated exists, where the compensation matrix database stores a crosstalk compensation matrix between any one qubit and a neighboring qubit of the qubit, where the crosstalk compensation matrix between any one qubit and the neighboring qubit of the qubit is calculated according to the compensation method for qubit driving crosstalk according to any one of claims 1-18;
The compensation module is used for existence of a crosstalk compensation matrix corresponding to the quantum bit to be operated in the compensation matrix database, and multiplying the actual superposition quantum state matrix by the crosstalk compensation matrix after target operation of the quantum bit to be operated to obtain an actual superposition quantum state matrix, so as to obtain a calculated result matrix after crosstalk compensation.
22. A quantum computer, comprising: at least one processor, and a memory storing a computer program executable on the processor, wherein the processor, when executing the program, performs the method of compensating for qubit drive crosstalk according to any of claims 1-18, or the method of qubit compensation according to claim 19.
23. A non-transitory readable storage medium storing a computer program, wherein the computer program when executed by a processor performs the method of compensating for qubit drive crosstalk according to any of claims 1-18 or the method of qubit compensation according to claim 19.
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