Abstract: Systems and methods are provided for performing a dynamic decoupled controlled-Z gate operation. A superconducting circuit of an exemplary system can include a first qubit and a second qubit transversely coupled to the first qubit, lire system can apply an external magnetic flux to the second qubit to bring a frequency of the second qubit into resonance with a frequency of the first qubit. The system can apply a continuous alternating drive with continuous phase to the second qubit, a duration and a magnitude of the continuous alternating drive configured to synchronize agate time of the dynamic decoupled controlled-Z gate operation to an integer number of Rabi oscillation periods. The system can read out a state of the quantum computing system, after providing the continuous alternating drive.

Abstract: The present disclosure discloses a method for determining fidelity of a qubit gate in a quantum processor, and a storage medium. The method includes: determining environmental qubit gates associated with a two-qubit gate in the quantum processor, where the two-qubit gate interacts with the environmental qubit gates in the quantum processor; determining a fidelity error of the environmental qubit gates based on a fidelity error of the two-qubit gate; determining frequency of the environmental qubit gates based on the fidelity error of the environmental qubit gates; and determining fidelity of the two-qubit gate based on the frequency of the environmental qubit gates. The present disclosure solves the technical problem of being unable to determine the fidelity of the two-qubit gate.

Abstract: This disclosure discloses a method for determining fidelity of a qubit gate in a quantum chip, and a storage medium. The method includes: determining environmental qubit gates associated with a two-qubit gate in the quantum chip, where the two-qubit gate interacts with the environmental qubit gates in the quantum chip; determining, based on the two-qubit gate and the environmental qubit gates, a first target matrix and a corresponding first evolution matrix, where the first target matrix is a diagonal matrix constructed based on a logic gate, and the first evolution matrix is a matrix obtained after time-dependent evolution; and determining the fidelity of the two-qubit gate based on the number of the environmental qubit gates associated with the two-qubit gate, the first target matrix, and the first evolution matrix. This disclosure solves the technical problem of being unable to determine the fidelity of the two-qubit gate.

Abstract: The present disclosure discloses method for determining decoherence model of qubit and computer readable storage medium. The method relates to the technical field of and quantum, including: acquiring decoherence measurement data obtained by performing decoherence measurement on the qubit; determining a plurality of type-parameter combinations, the type-parameter combinations that includes combinations of model types and model parameters; determining candidate decoherence models corresponding to the plurality of type-parameter combinations based on the decoherence measurement data; and determining a target decoherence model from the candidate decoherence models corresponding to the plurality of type-parameter combinations. According to the present disclosure, the technical problem of inaccurate prediction occurs when the decoherence time of the qubit is predicted by adopting the decoherence model in the conventional technology is solved.

Abstract: A method for generating a layout of a Josephson junction array includes obtaining an original script, in which geometric and action parameters are defined in the original script, the geometric parameters comprise a first structural parameter and a second structural parameter, the action parameters comprise an initial position parameter and a connection parameter; obtaining a first parameter value, a second parameter value, an initial position value, and a connection parameter value; in the original script, respectively assigning the first parameter value, the second parameter value, the initial position value, and the connection parameter value to the first structural parameter, the second structural parameter, the initial position parameter, and the connection parameter, so as to obtain a target script; and performing the target script to obtain a layout of a Josephson junction array having multiple connected Josephson junctions.

Abstract: A quantum layout optimization method includes: determining target Hamiltonian parameters of a quantum device; determining an initial quantum layout of the quantum device and initial geometric parameters of the initial quantum layout; determining a target gradient of Hamiltonian parameters of the quantum device to geometric parameters of the initial quantum layout; and adjusting the initial geometric parameters based on the target gradient to have the Hamiltonian parameters of the quantum device be the target Hamiltonian parameters to obtain a target quantum layout.

Abstract: A method for adjusting a resonant cavity includes: acquiring a construction parameter of a coplanar waveguide; determining, based on the construction parameter, an equivalent inductance of the coplanar waveguide, in which the equivalent inductance is a superposition of geometric inductance and kinetic inductance, and the equivalent inductance represents current density distribution on a metal surface of the coplanar waveguide; determining, based on the equivalent inductance, a resonance frequency of the resonant cavity formed by the coplanar waveguide, in which the resonance frequency is an analytical function with the construction parameter of the coplanar waveguide as a variable; and adjusting the resonance frequency of the resonant cavity to a target resonance frequency by adjusting a value of the construction parameter of the coplanar waveguide.

Abstract: A layout generation method includes: determining a quantum device type; acquiring an original script corresponding to the quantum device type, wherein a device parameter is defined in the original script; acquiring a target value of the device parameter; assigning the target value to the device parameter to obtain a target script of a target quantum device corresponding to the quantum device type; and generating, based on the target script, a quantum chip layout including the target quantum device.

Abstract: Methods and techniques are provided for simulating a quantum circuit. A system can perform operations including generating a transformed Hamiltonian corresponding to a quantum circuit. The transformed Hamiltonian can include transformed local and coupling Hamiltonians. Generation of the transformed Hamiltonian can include obtaining a charge coupling matrix and a flux coupling matrix of an original Hamiltonian corresponding to the quantum circuit and at least partially diagonalizing the charge coupling matrix and the flux coupling matrix. The operations can further include determining a limited eigenbasis including a number of eigenvectors of the transformed local Hamiltonian, projecting the transformed coupling Hamiltonian and the transformed local Hamiltonian onto the limited eigenbasis, and generating an at least partially decoupled Hamiltonian by combining the projection of the transformed coupling and local Hamiltonians.

Abstract: A method for optimizing a quantum circuit is disclosured. The method comprises acquiring a representation of a quantum circuit comprising one or more qubits, transforming, by linear transformation, first Hamiltonian corresponding to the quantum circuit to generate modes, generating a third Hamiltonian by removing the free modes from a second Hamiltonian in which free modes are decoupled from non-free the second Hamiltonian, simulating a behavior of the quantum circuit using the third Hamiltonian, and adjusting a design of the quantum circuit based on the simulated behavior of the quantum circuit.

Abstract: Qubit processing methods and apparatus, and a non-transitory computer readable medium are provided. The method includes determining a plurality of parts included in a qubit; determining electromagnetic interactions between the plurality of parts by using integral equations, to obtain electromagnetic parameters of surfaces of the plurality of parts, wherein the integral equations respectively use a Green's function to represent the electromagnetic interactions between the plurality of parts; and performing summation on the electromagnetic parameters of the surfaces of the plurality of parts to obtain an electromagnetic parameter of the qubit.