Noise spectroscopy of a quantum-classical environment with a diamond qubit
Name
PhysRevB.98.214307.pdf
Size
1.58 MB
Format
Adobe PDF
Checksum (MD5)
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Author(s)
Hernández-Gómez, S.
Poggiali, F.
Fabbri, N.
Cappellaro, Paola
Date Issued
December 2018
Journal
Physical Review B
Publisher
American Physical Society
Citation
Hernández-Gómez, S. et al. "Noise spectroscopy of a quantum-classical environment with a diamond qubit." Physical Review B 98, 21 (December 2018: 214307 © 2018 American Physical Society
Version
Final published version
Abstract
Knowing a quantum system's environment is critical for its practical use as a quantum device. Qubit sensors can reconstruct the noise spectral density of a classical bath, provided long enough coherence time. Here, we present a protocol that can unravel the characteristics of a more complex environment, comprising both unknown coherently coupled quantum systems, and a larger quantum bath that can be modeled as a classical stochastic field. We exploit the rich environment of a nitrogen-vacancy center in diamond, tuning the environment behavior with a bias magnetic field, to experimentally demonstrate our method. We show how to reconstruct the noise spectral density even when limited by relatively short coherence times, and identify the local spin environment. Importantly, we demonstrate that the reconstructed model can have predictive power, describing the spin qubit dynamics under control sequences not used for noise spectroscopy, a feature critical for building robust quantum devices. At lower bias fields, where the effects of the quantum nature of the bath are more pronounced, we find that more than a single classical noise model are needed to properly describe the spin coherence under different controls, due to the back action of the qubit onto the bath.
MIT Department
Massachusetts Institute of Technology. Department of Nuclear Science and Engineering
Terms of Use
Article is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use.
Persistent DSpace Link
DOI of Published Version
https://doi.org/10.1103/PhysRevB.98.214307
