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arXiv · 2307.04337

Detection of temporal fluctuation in superconducting qubits for quantum error mitigation

Yuta Hirasaki·Shunsuke Daimon·Toshinari Itoko·Naoki Kanazawa·Eiji Saitoh
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Abstract

We have investigated instability of a superconducting quantum computer by continuously monitoring the qubit output. We found that qubits exhibit a step-like change in the error rates. This change is repeatedly observed, and each step persists for several minutes. By analyzing the correlation between the increased errors and anomalous variance of the output, we demonstrate quantum error mitigation based on post-selection. Numerical analysis on the proposed method was also conducted.

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Yuta Hirasaki, Shunsuke Daimon, Toshinari Itoko, Naoki Kanazawa, Eiji Saitoh. 2023-07-10. Detection of temporal fluctuation in superconducting qubits for quantum error mitigation. https://doi.org/10.1063/5.0166739

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