Fig. 3: Exemplary resonance curves for each of the four hyperfine transitions.

a–d, The x axis is the difference of the frequency at which the spin-flip was driven and the expected resonance frequency at the simultaneously measured B field, assuming the Breit–Rabi equation with the theoretically calculated parameters. The green line is calculated from a maximum likelihood analysis assuming a Gaussian lineshape. Nuclear spin transitions \(|1\rangle \leftrightarrow |2\rangle \) (a) and \(|3\rangle \leftrightarrow |4\rangle \) (b), where the names of the states relate to the Breit–Rabi diagram in Fig. 1. Electron spin transitions \(|1\rangle \leftrightarrow |3\rangle \) (c) and \(|2\rangle \leftrightarrow |4\rangle \) (d). All error bars correspond to the \(1\sigma \) confidence interval (68%).