Fig. 7: Single-shot readout fidelity and QND-ness.
a Shows the qubit readout fidelity with respect to readout power. Here, the Pg∣g and Pe∣e are defined as the probability of preparing ground (excited) state and subsequently also measure the qubit to be in ground (excited) state. Ground and excited state initialization are implemented with a 200 μs waiting time and a 40 ns long gated microwave pulse, respectively. b Shows the QND-ness of this measurement as a function of \(\bar{n}\). Here, Pg,g and Pe,e are the probabilities to measure the ground and excited state consecutively in two independent 500ns long measurement pulses that are 1 μs apart, cf. Supplementary Fig. 5a. We note that the reported photon numbers correspond to calibrated steady state powers and do not reach the full value for a short readout pulse.
