Figure 2
From: Independent, extensible control of same-frequency superconducting qubits by selective broadcasting
Single-qubit control of same-frequency qubits using the VSM. (a, b) Schematics showing DRAG pulses routed exclusively to either QT or QB using the corresponding markers (always on or off). (c, d) Characterisation of single-qubit control by randomised benchmarking (RB) of Clifford gates. Average populations of QT and QB in the ground, first- and second-excited states (〈P0〉, 〈P1〉 and 〈P2〉, respectively) as a function of the number of Clifford gates applied. Curves are best fits of single exponentials with offsets. Single-qubit Clifford fidelities for each qubit are extracted from the decay of ground-state populations. Both surpass the surface-code fault-tolerance threshold and are near T1-only relaxation-limited performance. (e, f) Expanded plots of second-excited state leakage during RB. Curves are best fits according to equation (2). (g, h) Cross-excitation of the undriven qubit resulting from control pulses applied to the driven qubit due to microwave leakage.
