Mitigating measurement errors in multiqubit experiments

Sergey Bravyi, Sarah Sheldon, Abhinav Kandala, David C. Mckay, and Jay M. Gambetta
Phys. Rev. A 103, 042605 – Published 9 April 2021

Abstract

Reducing measurement errors in multiqubit quantum devices is critical for performing any quantum algorithm. Here we show how to mitigate measurement errors by a classical postprocessing of the measured outcomes. Our techniques apply to any experiment where measurement outcomes are used for computing expected values of observables. Two error-mitigation schemes are presented based on tensor product and correlated Markovian noise models. Error rates parametrizing these noise models can be extracted from the measurement calibration data using a simple formula. Error mitigation is achieved by applying the inverse noise matrix to a probability vector that represents the outcomes of a noisy measurement. The error-mitigation overhead, including the number of measurements and the cost of the classical postprocessing, is exponential in εn, where ε is the maximum error rate and n is the number of qubits. We report experimental demonstration of our error-mitigation methods on IBM Quantum devices using stabilizer measurements for graph states with n12 qubits and entangled 20-qubit states generated by low-depth random Clifford circuits.

  • Figure
  • Figure
  • Figure
  • Figure
  • Figure
  • Figure
  • Figure
  • Received 13 August 2020
  • Revised 10 February 2021
  • Accepted 22 March 2021

DOI:https://doi.org/10.1103/PhysRevA.103.042605

©2021 American Physical Society

Physics Subject Headings (PhySH)

Quantum Information, Science & Technology

Authors & Affiliations

Sergey Bravyi1, Sarah Sheldon2, Abhinav Kandala1, David C. Mckay1, and Jay M. Gambetta1

  • 1IBM Quantum, T. J. Watson Research Center, Yorktown Heights, New York 10598, USA
  • 2IBM Quantum, Almaden Research Center, San Jose, California 95120, USA

Article Text (Subscription Required)

Click to Expand

References (Subscription Required)

Click to Expand
Issue

Vol. 103, Iss. 4 — April 2021

Reuse & Permissions
Access Options
CHORUS

Article Available via CHORUS

Download Accepted Manuscript
Author publication services for translation and copyediting assistance advertisement

Authorization Required


×
×

Images

×

Sign up to receive regular email alerts from Physical Review A

Log In

Cancel
×

Search


Article Lookup

Paste a citation or DOI

Enter a citation
×