Crosstalk mitigation system and crosstalk mitigation method

Abstract

In a crosstalk mitigation system, crosstalk is reduced by simultaneously considering three factors: quantum circuits, the shuttle method, and the voltage application method. [Solution] A relational table is generated showing the voltage and state of the quantum dot based on the quantum dot's resonance frequency, the voltage dependence of the quantum dot's resonance frequency, hardware constraints, and distance function. An optimal quantum circuit is then selected based on the transpiled quantum circuit, the relational table, and hardware constraints to minimize crosstalk.

Claims

[Claim 1] A crosstalk mitigation system for mitigating crosstalk in quantum computers, A distance function generation unit generates a distance function that evaluates the magnitude of the crosstalk from the shift in the resonance frequency using a CPU, A relational table generation unit generates a relational table showing the voltage and state of a quantum dot based on the resonance frequency of the quantum dot, the voltage dependence of the resonance frequency of the quantum dot, hardware constraints, and the distance function, using a CPU. An optimal quantum circuit selection unit selects an optimal quantum circuit that minimizes crosstalk, based on the transpiled quantum circuit after the CPU has transpiled the user-desired quantum circuit so that it can be executed by the hardware, the relational table, and the hardware constraints. A crosstalk mitigation system characterized by having the following features. [Claim 2] The distance function generation unit is controlled by the CPU, The crosstalk mitigation system according to claim 1, characterized in that the distance function is generated based on the Hamiltonian from a predetermined metric that satisfies the triangle inequality. [Claim 3] The aforementioned relationship table generation unit is controlled by the CPU, The allowable voltage for the aforementioned quantum dot is calculated, The crosstalk mitigation system according to claim 1, characterized in that it generates the relational table for the set of quantum dots that take the same voltage value based on the hardware constraints. [Claim 4] The aforementioned optimal quantum circuit selection unit is controlled by the CPU, Based on the transpiled quantum circuit, the relational table, and the hardware constraints, the state of the quantum dot corresponding to the transpiled quantum circuit is determined. Based on the hardware constraints, the number of shuttle operations required to realize the arrangement of the quantum dots and qubits is determined. The voltage value of the quantum dot that matches the state of the quantum dot corresponding to the transpiler-post quantum circuit and the arrangement of the qubits is determined. The crosstalk mitigation system according to claim 1, characterized in that the optimal quantum circuit is selected by adjusting the arrangement of the qubits, the number of shuttle cycles, and the voltage value of the quantum dots so that the crosstalk is reduced. [Claim 5] The aforementioned optimal quantum circuit selection unit is controlled by the CPU, Using a cost function that takes into account the voltage change range, the number of shuttle operations, and the distance between the two qubits used in the two-qubit operation, The crosstalk mitigation system according to claim 4, characterized in that the arrangement of the qubits, the number of shuttle cycles, and the voltage value of the quantum dots are adjusted so as to minimize the value of the cost function. [Claim 6] The crosstalk mitigation system according to claim 4, characterized in that it has a display unit that displays the arrangement of the qubits adjusted by the optimal quantum circuit selection unit, the number of shuttles, the voltage value of the quantum dots, and the optimal quantum circuit, controlled by a CPU. [Claim 7] The crosstalk mitigation system according to claim 1, further comprising a visualization data generation unit that generates visualization data indicating the magnitude of the crosstalk based on the resonance frequency of the quantum dot, the voltage dependence of the resonance frequency of the quantum dot, the distance function, the voltage value of the quantum dot, and the optimal quantum circuit, using a CPU. [Claim 8] The aforementioned visualization data generation unit is controlled by the CPU, An approximation function of the aforementioned distance function is generated, The crosstalk mitigation system according to claim 7, characterized in that, based on the approximation function, the resonance frequency of the qubit, the gate operation, and the magnitude of the crosstalk for each reference time are generated as visualization data. [Claim 9] The visualization data generated by the visualization data generation unit is as follows: The crosstalk mitigation system according to claim 8, characterized in that it has a display unit that visualizes and displays the resonance frequency of the qubit, the gate operation, and the magnitude of the crosstalk. [Claim 10] A crosstalk mitigation method for mitigating crosstalk in a quantum computer, A distance function generation step in which the CPU generates a distance function to evaluate the magnitude of the crosstalk from the shift in the resonance frequency, A relational table generation step in which the CPU generates a relational table showing the voltage and state of the quantum dot based on the resonance frequency of the quantum dot, the voltage dependence of the resonance frequency of the quantum dot, hardware constraints, and the distance function, An optimal quantum circuit selection step in which the CPU selects the optimal quantum circuit that minimizes crosstalk, based on the transpiled quantum circuit after the user's desired execution quantum circuit has been transpiled by the CPU so that it can be executed by the hardware, the relational table, and the hardware constraints, A method for mitigating crosstalk, characterized by having the following features.

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