37 results about "Quantum logic" patented technology

The invention discloses a quantum computing fluid dynamics simulation method based on a lattice Boltzmann method, and the method combines the parallelism of quantum computing with the advantages of the lattice Boltzmann method. An efficient fluid dynamics solving framework is constructed through a collision operator in a non-equilibrium correction term linearization lattice Boltzmann equation which is obtained by deducing through a Chapman-Enskog theory and a Maxwell equilibrium state function, wherein the non-equilibrium correction term linearization lattice Boltzmann equation contains an adjustable relaxation parameter. The quantum state in the Hilbert space can be converted through a quantum logic gate due to the characteristics of quantum calculation, so that the problem of complex calculation in fluid mechanics is efficiently solved. According to the method, the actual problem is coded into the quantum state vector of the quantum bit, the vector is directly changed through quantum operation to solve the problem, the quantum bit state does not need to be iterated one by one, for example, in the matrix and vector multiplication process, operation can be completed only by using a quantum logic gate to act on the input quantum state, and therefore the calculation efficiency is remarkably improved.

The invention discloses an implementation method of a quantum logic gate and a quantum computer system. The method comprises the following steps: preparing a quantum bit to a preset initial quantum state; according to the Hamiltonian corresponding to the quantum logic gate, respectively generating microwave signals corresponding to each segment in the Hamiltonian; the Hamiltonian of the quantum logic gate comprises at least two segments, and the at least two segments are used for enabling quantum bits to generate at least one polarity reversal in evolution; the generated microwave signals corresponding to all the segments are spliced; and applying a spliced microwave signal to the quantum bits in the initial quantum state, so that the quantum bits evolve from the initial quantum state to a target quantum state. According to the invention, the quantum bit can generate at least one polarity change in evolution, partial phase dispersion is offset by using the polarity characteristic of 1 / f noise, decoherence is inhibited, and the fidelity of the single-bit quantum logic gate is further improved.

The invention discloses a normal distribution quantum state preparation method and device, and the method comprises the steps: preparing a quantum state of a first register from an initial state into a first quantum state representing a target value, and enabling the target value to be a value in a random variable value range after target normal distribution processing; preparing the quantum state of the second register from an initial state to a second quantum state representing a target value square; preparing a quantum state of a third register from an initial state to a third quantum state with an index including a target value square by using the second quantum state through a quantum logic gate combination for preparing an exponential distribution quantum state; and carrying out amplitude amplification on a superposition state comprising the first quantum state and the third quantum state to obtain a normal distribution quantum state. According to the embodiment of the invention, the normal distribution quantum state can be accurately prepared.

In a general aspect, a multi-qubit quantum logic gate for a multi-qubit hardware-efficient stabilizer measurement is performed. In some implementations, a superconducting quantum processing unit includes a stabilizer check qubit device and two or more data qubit devices operably coupled to the stabilizer check qubit device through respective tunable-frequency coupler devices. A method includes applying a multi-qubit quantum logic gate on the stabilizer check qubit device and the two or more data qubit devices. Applying the multi-qubit quantum logic gate includes evolving the stabilizer check qubit device and the two or more data qubit devices under an interaction Hamiltonian with a plurality of terms. Each of the plurality of terms corresponding to an interaction between the stabilizer check qubit device and a respective one of the two or more data qubit devices, includes a phase combined with a Pauli operator applied to the stabilizer check qubit device and the Pauli operator applied to the respective one of the two or more data qubit devices.

The disclosure is directed to characterizing a quantum logic circuit (QLC), via a set of intrinsic parameters. One method includes selecting control vectors that are associated with phase shifts for the intrinsic parameters such that experimental unitary operators for the QLC are defined. Each experimental unitary operator is based on the intrinsic parameters and phase shifts associated with a corresponding control vector. For each control vector, eigenvalues for the corresponding unitary operator are estimated based on qubit measurements performed subsequent to tuning the QLC in accordance with the control vector. The eigenvalues correspond to quasienergy levels of the qubits. Values for the set of intrinsic parameters may be determined based on the eigenvalues.

Pulse-generator-based reciprocal quantum logic (RQL) bias-level sensors are fabricated on an RQL integrated circuit (IC) to sample AC or DC bias values provided to operational RQL circuitry on the RQL IC. The bias-level sensors include pulse generators having strengthened or weakened bias taps (transformer couplings to RQL AC clock resonators or DC bias lines) as compared to bias taps of Josephson transmission lines in the operational RQL circuitry, or Josephson junctions (JJs) with larger or smaller critical currents as compared to JJs in the operational RQL circuitry. Pulse generators with weakened bias taps or larger JJs can have lower limits of their operational ranges placed near an optimal bias point at the centroid of the operating region of the operational RQL circuitry. The bias-level sensors can be staged by relative strength to indicate whether a provided bias value is an improvement when varied over a range.

The invention discloses a quantum state coding method of a polynomial function and a related device, and belongs to the technical field of quantum computing, and the method comprises the steps: determining the scale of a unitary matrix based on the highest order of the polynomial function, and constructing a target matrix based on a plurality of function values of the polynomial function; wherein the quantum logic gate corresponding to the unitary matrix is used for constructing a quantum circuit of a quantum state of a coding polynomial function, and the line number of the target matrix is the same as that of the unitary matrix; performing singular value decomposition on the target matrix to obtain a plurality of unitary matrixes; and determining a quantum logic gate corresponding to each unitary matrix, and acting each quantum logic gate on the corresponding quantum bit to obtain the quantum state of the polynomial function, thereby realizing coding from the classical data form to the quantum state of the polynomial function.

The invention discloses a method and device for calculating energy of a target system and a medium, and the method comprises the steps: firstly, determining a Fermi-form Hartree Fock state of the target system, then constructing a quantum phase estimation line, generating a control pulse of a quantum logic gate in the quantum phase estimation line, and calculating the energy of the target system according to the control pulse. The method comprises the following steps of: constructing a quantum phase estimation circuit capable of being used for current quantum computing hardware equipment, enabling a control pulse to act on a quantum bit in the quantum phase estimation circuit to evolve the specified quantum bit from a Hartree Fock state to a target quantum state, and finally calculating ground state energy of a target system according to the Hartree Fock state and the target quantum state, so that the ground state energy of the target system is calculated by constructing the quantum phase estimation circuit capable of being used for the current quantum computing hardware equipment. The method provides support for realizing quantum chemistry simulation calculation of target system energy, improves calculation speed and calculation precision, and promotes simulation calculation of target system ground state energy.

The present invention discloses a method, apparatus, storage medium, and electronic device for preparing a normally distributed quantum state, which are applied to the field of quantum computing. The method includes: obtaining a first preset parameter and a second preset parameter; wherein the first preset parameter is used to represent the preparation accuracy of the normally distributed quantum state, and the second preset parameter is used to represent the distribution law of the normally distributed state; based on the first preset parameter, the number n of quantum bits used to prepare the normally distributed quantum state can be determined; based on the second preset parameter, the rotation parameter of each quantum bit can be determined, and the PY gate operation corresponding to the rotation parameter is performed on each of the n quantum bits in the initial state; and then a summation operation is performed on the n quantum bits to obtain the normally distributed quantum state. Compared with the commonly used method of preparing normally distributed quantum states based on bisection, this solution reduces the number of quantum logic gates and computational complexity required to prepare the quantum state, thereby meeting the demand for efficient preparation of normally distributed quantum states.

The present invention provides a method for quantum phase estimation, including: generating a first quantum logic gate sequence according to a problem to be solved and determining an initial quantum state; adding a random quantum gate to the first quantum logic gate sequence to generate a second quantum logic gate sequence; applying the second quantum logic gate sequence to the initial quantum state and measuring the final quantum state; performing a discrete Fourier transform on the measurement result to obtain a phase estimation value. The method for quantum phase estimation and the system for quantum phase estimation provided by the present invention convert the coherent noise and decoherent noise between quantum bits into random Pauli noise through secondary compilation. Due to the statistical characteristics of random Pauli noise, the noise of quantum phase estimation performed using the method for quantum phase estimation or the system for quantum phase estimation is reduced, and the accuracy of quantum phase estimation is improved, thereby realizing a universal and feasible solution for noise-resistant quantum phase estimation.

The invention discloses a quantum computer-oriented evolutionary quantum architecture search method, which comprises the following steps of: constructing a search space by adopting different quantum logic gates according to different image data sets; initializing the quantum gate combination candidate set in the search space, and generating a circuit structure feature code; evaluating the initialized quantum gate combination candidate set on the data set, and obtaining the fitness ranking of each quantum gate combination on the current image processing task; dynamically adjusting the elite proportion by using an adaptive binary bidding selection algorithm, preferentially retaining a high-potential and high-fitness framework, and filling a mating pool; an inheritable mutation algorithm is adopted, directional mutation is performed according to difference sites while information continuity of a parent structure is kept, convergence is accelerated, and population diversity is improved; under the condition that quantum bit resources are met, evolution iteration and parameter fine tuning are adopted for alternate optimization, and a self-adaptive double-threshold small-angle pruning method is designed to reduce the gate number and the circuit depth.

Systems and methods for quantum computing devices are provided. In one example, a method may include implementing, by a quantum computing system, a microwave pulse train in a microwave control signal for a qubit of a quantum computing system, the microwave pulse train having a plurality of microwave pulses. The method may include determining, by the quantum computing system, a Fourier parameter associated with the plurality of microwave pulses based at least in part on a Rabi oscillation of the qubit. The method may include modifying, by the quantum computing system, one or more control signals for the qubit of the quantum computing system based at least in part on the Fourier parameter.

Methods, systems and apparatus for estimating the fidelity of quantum logic gates. In one aspect, a method includes defining multiple sets of random quantum circuits; for each set of random quantum circuits: selecting an observable for each element in the set of random quantum circuits, wherein each selected observable corresponds to a respective element of the set of random quantum circuits and is dependent on the element to which it corresponds; estimating a value of a polarization parameter for the set of random quantum circuits, comprising performing a least mean squares minimization based on multiple expectation values, wherein each expectation value comprises an expectation value of a respective selected observable with respect to an output of an experimental implementation of a random quantum circuit corresponding to the respective selected observable; and processing the estimated polarization parameter values to obtain an estimate of the fidelity of the n-qubit quantum logic gate.

The invention discloses a quantum neural network training method and a related device. The method comprises the following steps: acquiring a quantum logic gate sequence; setting at least one check point from the quantum logic gate sequence according to a certain number of interval nodes, and storing quantum state intermediate data obtained by forward propagation calculation of the at least one check point into a memory; if the current computing node is not the check point and the check point exists before the current computing node, backtracking to the nearest check point from the current computing node, and reading the quantum state intermediate data of the nearest check point from the memory; and performing reverse calculation based on the quantum state intermediate data of the closest check point to update parameters in the quantum neural network so as to realize training of the quantum neural network. By introducing a check point setting mechanism, the memory consumption in the quantum neural network training process is reduced, so that the resource space configuration is optimized, and the model training efficiency is improved.

One example aspect of the present disclosure is directed to a method for implementing fault-tolerant quantum computing. The method includes receiving a set of inputs for a fault-tolerant quantum-computation circuit (QCC). The set of inputs includes an indication of a set of logical qubits and an indication of a set of quantum-logic stabilizers that the QCC is configured to perform on the set of logical qubits. A satisfiability modulo theory (SMT) model for the QCC is generated based on the set of inputs. The SMT model includes a set of constraints. A set of values to populate a data structure. The set of values satisfies the set of constraints of the SMT model. The data structure populated by the set of values encodes an intermediate representation (IR) of a time evolution of the QCC performing the set of quantum-logic stabilizers on the set of logical qubits.

A quantum logic spectroscopy system for an ion trap configured to trap a primary ion and a detection ion, the quantum logic spectroscopy system configured to apply one or more conditioning operations, each of the one or more conditioning operations comprising applying a mapping operation to map a primary ion state of the primary ion on to a detection ion state of the detection ion, applying a state change operation comprising changing the detection ion state if the detection ion state has a first detection state value, and determine a probability of the detection ion state changing in response to the application of the state change operation, and determine the primary ion state using the determined probability or determine that the primary ion state is indeterminate using the determined probability.

The invention discloses an amplitude preparation method of a quantum state and a related device, and belongs to the technical field of quantum computing, the method comprises the following steps: determining each partial component of a target quantum state to be prepared, each partial component comprising a ground state of the target quantum state and a probability amplitude of the ground state; a plurality of target matrixes are constructed based on the probability amplitudes of the partial components, singular value decomposition is carried out on the target matrixes to obtain unitary matrixes, and quantum logic gates corresponding to the unitary matrixes obtained through decomposition act together to evolve a target quantum state into 0gt; state; constructing inverse mapping of quantum logic gates corresponding to the unitary matrixes, and acting on the initial state 0gt; an amplitude preparation quantum circuit is obtained on the quantum bit of the state, and the amplitude preparation quantum circuit is used for generating the target quantum state. According to the scheme, the amplitude preparation quantum circuit is constructed based on the idea of deentanglement, and the amplitude preparation of the quantum state can be more efficiently carried out.

The application discloses a quantum state preparation method and device, and the method comprises the following steps: first, obtaining an N-dimensional second data vector to be prepared; then, constructing a quantum state preparation circuit; finally, generating a control pulse of a quantum logic gate in the quantum state preparation circuit, and applying the control pulse to a quantum bit in the quantum state preparation circuit, so that the quantum bit evolves from an initial state to a second quantum state |Ψ e > through a first quantum state |Ψ t >, which reduces the number of quantum state preparation amplitude amplifications, reduces the depth and operation number of the quantum state preparation circuit by constructing the quantum state preparation circuit.

The invention discloses a prediction type high-fidelity entangled quantum logic gate method, which is suitable for quantum computing physical systems such as neutral atom quantum bits and superconducting quantum bits. According to the method, on the basis of a multi-body physical system formed by coupling mediating atoms with quantum bit atoms, a special modulation waveform driving system with space-time symmetry is designed according to the requirement for realizing a two-bit entangled quantum logic gate; the induction quantum interference effect enables the specific quantum internal state of the mediating atom to correspond to the quantum state of which the error first-order effect of the whole quantum logic gate of the system is subjected to mutual interference cancellation after the driving is finished; thus, by measuring the quantum internal state of the mediating atom, a specific measurement result can forecast that the high-fidelity quantum logic gate has been established between two quantum bit atoms. According to the method, errors can be suppressed and relieved on a quantum computing hardware level, so that a forecast type high-fidelity two-bit quantum logic gate is implemented, a high-quality hardware basis can be provided for an advanced quantum error correction algorithm, and the method has important significance in realizing high-fidelity quantum computing.

The application discloses a construction method and device of a quantum circuit corresponding to a linear function, and the method comprises the following steps: preparing an independent variable of a target linear function on a first quantum bit; obtaining a second quantum bit used for outputting the target linear function, adding a parametric quantum logic gate acting on the second quantum bit, and controlling the parametric quantum logic gate through the first quantum bit; determining a parameter value of the parametric quantum logic gate according to the target linear function, and obtaining the quantum circuit corresponding to the target linear function. By using the embodiment of the application, the linear function can be represented in the field of quantum computation, and the blank of related technologies is filled.

The embodiment of the invention discloses a quantum circuit construction method for predicting the optimal state of a system and a related device, and the method comprises the steps: enabling a Hadamard gate to act on a first register, enabling a first group of variable component sub-logic gates virtually controlled by the first register to act on a second register, a third register and a fourth register, and enabling a second group of variable component sub-logic gates to act on a fourth register; enabling a second group of variable component sub logic gates actually controlled by the first register to act on a second register, a third register and a fourth register, enabling a NOT gate actually controlled by the first register and the third register to act on the fourth register, and enabling a Hadamard gate to act on the first register to obtain a target quantum circuit; the target quantum circuit is used for determining the optimal state of the system at the current moment according to the observation probability of the quantum state of the first register, the embodiment of the invention discloses a specific quantum circuit for predicting the optimal state of the system, and estimation of the optimal state of the system is facilitated.

The embodiment of the invention provides a quantum state reading method, a quantum calculation measurement and control system and a storage medium. According to the scheme, the method comprises the following steps: obtaining quantum measurement and control information required by a target quantum bit to execute a target quantum logic gate operation; based on the first waveform parameter, obtaining a quantum state reading result of the target quantum bit at the current moment through a reading signal line, and taking the quantum state reading result as a first reading result; based on the second waveform parameter, triggering the target quantum bit to execute a target quantum logic gate operation through the bit signal line; based on the first waveform parameter, obtaining a quantum state reading result after the target quantum bit completes the target quantum logic gate operation through a reading signal line, and taking the quantum state reading result as a second reading result; and when the first reading result is the target quantum state, determining the second reading result as a target reading result corresponding to the target quantum logic gate operation. Through the technical scheme provided by the embodiment of the invention, the accuracy of a quantum state reading result is improved.

To provide a quantum logic gate operation device, a method and a program which have quick gate execution speed while holding heat insulation performance, and realize entanglement quantum gate operation being resistive to ZI interaction error, residual ZZ interaction error and phase relaxation error.SOLUTION: A quantum logic gate operation device comprises: a 2 quantum bit system of a control quantum bit 11 and a target quantum bit 12; a crossing resonance drive pulse irradiation unit which irradiates the control quantum bit with crossing resonance drive pulses of a natural frequency of the target quantum bit; an echo pulse irradiation unit which irradiates the control quantum bit with echo pulses which reverse a quantum state; and a control unit which emits the crossing resonance drive pulses of a first phase in a first period of quantum logic gate operation, continuously changes the phase while holding strength of the pulses in a second period, controls the crossing resonance drive pulse irradiation unit so as to emit the crossing resonance drive pulses of a second phase in a third period, and controls the echo pulse irradiation unit so as to irradiate the echo pulses in the second period.SELECTED DRAWING: Figure 5

The invention discloses a pseudo-random prediction-based quantum bit waveform parameter dynamic configuration method and system, and relates to the technical field of superconducting quantum calculation measurement and control, and the method comprises the steps: a configuration execution circuit decodes prediction code words generated on a chip to obtain a parameter group index, the prediction code words are generated by a pseudo-random prediction engine, and the parameter group index is generated by a pseudo-random prediction engine; the pseudo-random prediction engine receives externally input seed data by using a seed stack and executes a pseudo-random algorithm in real time by using a real-time prediction module, and a pseudo-random numerical value obtained by prediction serves as a prediction code word corresponding to a measurement and control waveform of next quantum logic gate operation in a quantum bit line according to a set rule; parameter group indexes are used for carrying out parallel search in a parameter lookup table of a configuration execution circuit, all parameter data values corresponding to the parameter group indexes can be output after a clock period, and therefore quantum bit measurement and control waveforms mapped by the parameter data are dynamically configured. The parameter dynamic configuration method and system aim at achieving efficient and low-delay quantum bit measurement and control waveform configuration.

In a first aspect, a method for suppressing rotating implementation errors in a multi-qubit quantum logic operation G. The method comprising applying at least one of a corresponding single-qubit prefix gate, before applying said quantum logic operation G; and, a corresponding single-qubit suffix gate, after applying said quantum logic operation G. Coefficients of Pauli terms, of any one of said prefix gate and said suffix gate, are based on an accumulated time from a beginning of a quantum circuit to the quantum logic operation G. In a second and aspect, a method for rotating dynamical-decoupling for pair-wise application of a quantum logic operation G. In further aspects, a characterization method for rotating implementation errors, and systems for implementation of the methods.

The invention belongs to the technical field of quantum computing, and discloses a quantum residual attention neural network, which comprises a quantum embedding layer based on a quantum logic gate and used for encoding input data into an initial quantum state; the variable component sub-circuit is used for acting on the initial quantum state in combination with the auxiliary quantum state, realizing evolution of the quantum state and performing quantum state feature extraction; and the quantum measurement layer is used for carrying out measurement through a Fouli Z gate according to the quantum state characteristics output by the variable component sub-circuit to obtain output data. The invention also provides a material design method. The method comprises the following steps: acquiring material component data; performing dimension reduction processing on the material component data to obtain dimension-reduced material component feature data; and inputting the material component characteristic data into the quantum residual attention neural network to obtain material performance prediction data. According to the method, generalization of the neural network is provided, and high accuracy can be obtained under the condition of a small number of training samples.

The invention discloses a construction method of an arbitrary non-adiabatic sum quantum logic gate of a rare earth ion system, and relates to the technical field of quantum computing. Comprising the following steps: firstly, designing a beveling evolution path with a degree of freedom in a Bloch ball; the degree of freedom is beveled; the evolution path is a random path; converting the evolution path into the amplitude and phase parameters of the optical pulse required for controlling the three-energy-level system through reverse engineering; then generating a group of double-color light pulses by using an arbitrary wave generator and an acousto-optic modulator based on the amplitude and phase parameters; and finally, controlling the quantum state coupled by the light field by using the two-color light pulse so as to construct the non-adiabatic harmony quantum logic gate. The constructed logic gate shows relatively strong robustness to inherent frequency detuning (non-uniform broadening) of an ensemble system and light intensity distribution errors in an experiment, and the accuracy and stability of quantum control in an actual noise environment are remarkably improved.

The invention relates to quantum information technology demonstration, in particular to a single-bit quantum logic gate operation simulation demonstration method, which comprises the following steps: selecting a function mode, and entering a concept demonstration mode / analysis demonstration mode; after entering a concept demonstration mode, selecting an initial state of a quantum bit and a quantum logic gate, and after operation, performing spatial conversion on the position of the initial state in a Bloch sphere by using a Bloch sphere view angle of the quantum logic gate to obtain and display the position of a final state of the quantum bit in the Bloch sphere; after entering an analysis demonstration mode, selecting an initial state and a quantum logic gate of the quantum bit, obtaining a column vector of the initial state and a matrix of the quantum logic gate after operation, calculating a column vector of a final state of the quantum bit according to an analysis demonstration mode calculation kernel, and converting the column vector of the final state into a space coordinate of a corresponding Bloch sphere; column vector display and Bloch ball display of a final state are carried out; the technical scheme provided by the invention can effectively overcome the defect that learning requirements at different stages are difficult to consider in the prior art.

The embodiment of the invention provides a quantum state reading method, a quantum calculation measurement and control system and a storage medium. The method comprises the following steps: obtaining quantum measurement and control information; after the first time delay at the current moment, based on the first waveform parameter and the second time delay, triggering a first reading operation for the quantum state of the target quantum bit at the current moment through the reading signal line to obtain a first reading result; based on the second waveform parameter, triggering the target quantum bit to execute a target quantum logic gate operation through the bit signal line; based on the first waveform parameter and the second time delay, triggering a second reading operation of the quantum state after the target quantum bit completes the target quantum logic gate operation through the reading signal line, and obtaining a second reading result; and when the first reading result is the target quantum state, determining the second reading result as a target reading result corresponding to the target quantum logic gate operation. Through the technical scheme provided by the embodiment of the invention, the fidelity of quantum state reading is improved.

The present invention discloses a method and system for dynamic configuration of quantum bit waveform parameters based on pseudo-random prediction, which relates to the field of superconducting quantum computing measurement and control technology. The method comprises: a configuration execution circuit decodes a prediction codeword generated on a chip to obtain a parameter group index, the prediction codeword is generated by a pseudo-random prediction engine, the pseudo-random prediction engine uses a seed stack to receive seed data input from an external source, and uses a real-time prediction module to execute a pseudo-random algorithm in real time. The predicted pseudo-random value is used as the prediction codeword corresponding to the measurement and control waveform of the next quantum logic gate operation in the quantum bit circuit according to a set rule; the parameter group index is used to perform a parallel search in a parameter lookup table of the configuration execution circuit, and all parameter data values ​​corresponding to the parameter group index can be output in one clock cycle, thereby dynamically configuring the quantum bit measurement and control waveform mapped by the parameter data; the method and system for dynamic parameter configuration are intended to achieve efficient and low-latency quantum bit measurement and control waveform configuration.