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arXiv · 2303.06496

Locality and Error Mitigation of Quantum Circuits

Minh C. Tran·Kunal Sharma·Kristan Temme
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Abstract

In this work, we study and improve two leading error mitigation techniques, namely Probabilistic Error Cancellation (PEC) and Zero-Noise Extrapolation (ZNE), for estimating the expectation value of local observables. For PEC, we introduce a new estimator that takes into account the light cone of the unitary circuit with respect to a target local observable. Given a fixed error tolerance, the sampling overhead for the new estimator can be several orders of magnitude smaller than the standard PEC estimators. For ZNE, we also use light-cone arguments to establish an error bound that closely captures the behavior of the bias that remains after extrapolation.

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Minh C. Tran, Kunal Sharma, Kristan Temme. 2023-03-11. Locality and Error Mitigation of Quantum Circuits. https://arxiv.org/abs/2303.06496

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