(a) Measured coupling strength, g/2π versus coupler bias (dots) in comparison with the numerical calculation (line). (b) Experimental pulse sequence used for the qubit–resonator swap dynamics, where qubit is excited to | 1 〉 at 5.63 GHz and then biased with ZPA to a fixed frequency around the resonator for energy exchange process. (c) Qubit | 1 〉 state probability, P₁ (color bar on the far right) and delay time versus qubitʼs ZPA, measured with the experimental pulse sequence shown in panel (b) at three coupler biases as numbered in panel (a). The coupling strength is estimated from Fourier transform of the data in panel (c) (For clarity in display the y scales are different for the color plots).