arXiv:2402.12361 · Physical Review Applied

Multiaxis quantum noise spectroscopy robust to errors in state preparation and measurement

Muhammad Qasim Khan, Wenzheng Dong, Leigh Norris, Lorenza Viola

Published Aug 29, 2024• 11 citations

Abstract

Quantum noise spectroscopy (QNS) is a powerful tool to characterize temporally correlated environmental noise, for noise-tailored control in noisy intermediate-scale quantum processors. However, QNS protocols have been limited by their vulnerability to state-preparation-and-measurement (SPAM) errors, and their inability to simultaneously characterize dephasing and relaxation effects. This work overcomes both of these challenges. The authors present a single-qubit QNS protocol utilizing continuous off-axis control for robust estimation of all multiaxis noise spectra, and show that SPAM errors can significantly alter or mask important features of the underlying native noise.

DOI: 10.1103/physrevapplied.22.024074

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