Fig. 4: Coherent acoustic control of the SiV spin qubit.

a Pulse sequence used for Rabi oscillation measurements. An acoustic pulse of frequency \(3.43\ {\text{GHz}}\), which is resonant with the SiV spin transition and generated with \(2\ {\text{mW}}\) peak microwave input power, is used to coherently drive the qubit. b Normalized population in the \(\left|\downarrow \right\rangle\) state as the acoustic pulse duration is varied. A fit to a theoretical model is shown in red. (Inset) The dependence of Rabi frequency on the square root of peak microwave input power indicates the expected linear behavior. The errors in the Rabi frequencies are of the order of \(0.1\ {\text{MHz}}\). c Pulse sequence used for Ramsey interferometry measurements. Two \(\pi /2\) acoustic pulses, each detuned by \(50\ {\text{MHz}}\) and generated with \(4\ {\text{mW}}\) peak input power, are separated by a varying free precession time. d Normalized population in the \(\left|\downarrow \right\rangle\) state as the free precession time is varied. A fit to a theoretical model is shown in red. The time constant of the exponential decay of the oscillations gives a spin coherence time \({T}_{2}^{* }=33\pm 5\ {\text{ns}}\). The error bars in b and d represent the standard deviation of the normalized population.