Environmental noise spectroscopy with qubits subjected to dynamical decoupling

  title={Environmental noise spectroscopy with qubits subjected to dynamical decoupling},
  author={Piotr Szankowski and Guy Z. Ramon and Jan A. Krzywda and Damian Kwiatkowski and Łukasz Cywiński},
  journal={Journal of Physics: Condensed Matter},
A qubit subjected to pure dephasing due to classical Gaussian noise can be turned into a spectrometer of this noise by utilizing its readout under properly chosen dynamical decoupling (DD) sequences to reconstruct the power spectral density of the noise. We review the theory behind this DD-based noise spectroscopy technique, paying special attention to issues that arise when the environmental noise is non-Gaussian and/or it has truly quantum properties. While we focus on the theoretical basis… 

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