Driving Ge hole spin qubit using acoustic wave

Germanium hole spin qubits based on strained Ge/SiGe quantum well, owing to their relatively long coherence time, scalability and strong spin-orbit coupling, have become a versatile platform for quantum information processing. In particular, the strain dependence of the LH(light hole)-HH(heavy hole) mixing and thus the g tensor anisotropy offers unique opportunities for spin-phonon coupling. In this work we first performed theoretical simulation to study the coherent control of a Ge hole spin qubit under a periodic strain modulation caused by surface acoustic waves (SAWs). The periodic strain modulates the g tensor matrix and leads to time-dependent 'tilting' of the g tensor peanut-like shape. Therefore, the spin state is driven by the g tensor modulation when the Zeeman energy matches the acoustic wave frequency. We analyzed the acoustic driving Rabi oscillation frequency as a function of the angle between the external magnetic field and the SAW direction and found a striking driving anisotropy owing to SAW-induced strain components. Next, we will present our progress in the experiment. This work provides new insights into acoustic-driven spin control and spin-phonon coupling using Ge hole spin qubits.