Dataset Information

Multi-level quantum noise spectroscopy.

ABSTRACT: System noise identification is crucial to the engineering of robust quantum systems. Although existing quantum noise spectroscopy (QNS) protocols measure an aggregate amount of noise affecting a quantum system, they generally cannot distinguish between the underlying processes that contribute to it. Here, we propose and experimentally validate a spin-locking-based QNS protocol that exploits the multi-level energy structure of a superconducting qubit to achieve two notable advances. First, our protocol extends the spectral range of weakly anharmonic qubit spectrometers beyond the present limitations set by their lack of strong anharmonicity. Second, the additional information gained from probing the higher-excited levels enables us to identify and distinguish contributions from different underlying noise mechanisms.

SUBMITTER: Sung Y

PROVIDER: S-EPMC7878521 | biostudies-literature | 2021 Feb

REPOSITORIES: biostudies-literature

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Publications

Multi-level quantum noise spectroscopy.

Sung Youngkyu Y Vepsäläinen Antti A Braumüller Jochen J Yan Fei F Wang Joel I-Jan JI Kjaergaard Morten M Winik Roni R Krantz Philip P Bengtsson Andreas A Melville Alexander J AJ Niedzielski Bethany M BM Schwartz Mollie E ME Kim David K DK Yoder Jonilyn L JL Orlando Terry P TP Gustavsson Simon S Oliver William D WD

Nature communications 20210211 1

System noise identification is crucial to the engineering of robust quantum systems. Although existing quantum noise spectroscopy (QNS) protocols measure an aggregate amount of noise affecting a quantum system, they generally cannot distinguish between the underlying processes that contribute to it. Here, we propose and experimentally validate a spin-locking-based QNS protocol that exploits the multi-level energy structure of a superconducting qubit to achieve two notable advances. First, our pr ...[more]

PMID: 33574240

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Dataset Information

Multi-level quantum noise spectroscopy.

Publications

Multi-level quantum noise spectroscopy.

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