Table 1 Parameters obtained after fitting the measured fidelities of systems prepared in states \(|{\Psi _{1}}\rangle =(|{01}\rangle +|{10}\rangle )/\sqrt{2}\), \(|{\Psi _{2}}\rangle =(|{001}\rangle +|{010}\rangle +|{100}\rangle +|{111}\rangle )/2\) and \(|{\Psi _{3}}\rangle =(|{001}\rangle +|{010}\rangle +|{100}\rangle +|{111}\rangle )/2\) after application of \(N\in [1,600]\) LEOs to the linear function in Eq. (11).

From: Implementation of leakage elimination operators and subspace protection

 

\(a_{i}\)

\(b_{i}\)

\(f_{1}^{\text {lin}}\)

\((8.75\pm 0.01) \times 10^{-1}\)

\((1.4\pm 0.4) \times 10^{-5}\)

\(f_{2}^{\text {lin}}\)

\((6.60\pm 0.01)\times 10^{-1}\)

\((1.0\pm 0.4)\times 10^{-5}\)

\(f_{3}^{\text {lin}}\)

\((9.81\pm 0.01)\times 10^{-1}\)

\((-3\pm 3)\times 10^{-6}\)

  1. The specific LEOs we used are Z for \(|{\Psi _{1}}\rangle\) and \(|{\Psi }\rangle _{2}\) and CNOT for \(|{\Psi _{3}}\rangle\).