Figure 3

Simulation of the deconvolution process for the general Pauli channel \(\mathcal{N}_{\boldsymbol{p}}\) (40). The noise parameters along the three Pauli axes are set to \(p_{x}=0.1\), \(p_{y}=0.05\), \(p_{z}=0.2\). The results are obtained simulating the circuit portrayed on top of the image for \(n_{\text{shots}} = 1024\) shots and for multiple values of the angle θ. Then, the deconvolution formulas (42) are used to retrieve the ideal noise-free result. It is clear that the deconvolution effectively mitigates the Pauli noise yielding a final result which is much closer to the ideal noise-free one, up to differences due to stochastic measurement outcomes. In particular, the estimation of \(\sigma _{y}\) is dominated by the statistical error, which is amplified by the correction factor \(1/(1-2(p_{x}+p_{z})) = 2.5\)