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arXiv · 2108.12518

Scalable mitigation of measurement errors on quantum computers

Paul D. Nation·Hwajung Kang·Neereja Sundaresan·Jay M. Gambetta
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Abstract

We present a method for mitigating measurement errors on quantum computing platforms that does not form the full assignment matrix, or its inverse, and works in a subspace defined by the noisy input bit-strings. This method accommodates both uncorrelated and correlated errors, and allows for computing accurate error bounds. Additionally, we detail a matrix-free preconditioned iterative solution method that converges in $\mathcal{O}(1)$ steps that is performant and uses orders of magnitude less memory than direct factorization. We demonstrate the validity of our method, and mitigate errors in a few seconds on numbers of qubits that would otherwise be intractable.

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Paul D. Nation, Hwajung Kang, Neereja Sundaresan, Jay M. Gambetta. 2021-08-27. Scalable mitigation of measurement errors on quantum computers. https://doi.org/10.1103/prxquantum.2.040326

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