English

Fundamental limits of quantum error mitigation

Quantum Physics 2022-09-23 v5

Abstract

The inevitable accumulation of errors in near-future quantum devices represents a key obstacle in delivering practical quantum advantages, motivating the development of various quantum error-mitigation methods. Here, we derive fundamental bounds concerning how error-mitigation algorithms can reduce the computation error as a function of their sampling overhead. Our bounds place universal performance limits on a general error-mitigation protocol class. We use them to show (1) that the sampling overhead that ensures a certain computational accuracy for mitigating local depolarizing noise in layered circuits scales exponentially with the circuit depth for general error-mitigation protocols and (2) the optimality of probabilistic error cancellation among a wide class of strategies in mitigating the local dephasing noise on an arbitrary number of qubits. Our results provide a means to identify when a given quantum error-mitigation strategy is optimal and when there is potential room for improvement.

Keywords

Cite

@article{arxiv.2109.04457,
  title  = {Fundamental limits of quantum error mitigation},
  author = {Ryuji Takagi and Suguru Endo and Shintaro Minagawa and Mile Gu},
  journal= {arXiv preprint arXiv:2109.04457},
  year   = {2022}
}

Comments

12+10 pages, 10 figures. v5: extended the results on protocol benchmarking; published version

R2 v1 2026-06-24T05:50:13.618Z