Szańkowski P, Ramon G, Krzywda J, Kwiatkowski D, Cywiński Ł
Institute of Physics, Polish Academy of Sciences, Aleja Lotnikow 32/46, PL-02668 Warsaw, Poland.
J Phys Condens Matter. 2017 Aug 23;29(33):333001. doi: 10.1088/1361-648X/aa7648. Epub 2017 Jun 1.
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 of the method, we connect the discussed concepts with specific experiments, and provide an overview of environmental noise models relevant for solid-state based qubits, including quantum-dot based spin qubits, superconducting qubits, and NV centers in diamond.
由于经典高斯噪声而经历纯退相的量子比特，可以通过在适当选择的动态解耦（DD）序列下利用其读出，来重建噪声的功率谱密度，从而转变为这种噪声的光谱仪。我们回顾了这种基于DD的噪声光谱技术背后的理论，特别关注当环境噪声是非高斯的和/或具有真正量子特性时出现的问题。虽然我们专注于该方法的理论基础，但我们将所讨论的概念与具体实验联系起来，并概述了与基于固态的量子比特相关的环境噪声模型，包括基于量子点的自旋量子比特、超导量子比特和金刚石中的氮空位中心。
