Ultrafast and Electrically Tunable Rabi Frequency in a Germanium Hut Wire Hole Spin Qubit

Hole spin qubits based on germanium (Ge) have strong tunable spin-orbit interaction (SOI) and ultrafast qubit operation speed. Here we report that the Rabi frequency (f Rabi) of a hole spin qubit in a Ge hut wire (HW) double quantum dot (DQD) is electrically tuned through the detuning energy (6) and middle gate voltage (VM). fRabi gradually decreases with increasing 6; on the contrary, f Rabi is positively correlated with VM. We attribute our results to the change of electric field on SOI and the contribution of the excited state in quantum dots to fRabi. We further demonstrate an ultrafast f Rabi exceeding 1.2 GHz, which indicates the strong SOI in our device. The discovery of an ultrafast and electrically tunable fRabi in a hole spin qubit has potential applications in semiconductor quantum computing.

Automated summary

Hole spin qubits based on germanium have strong tunable spin-orbit interaction and ultrafast qubit operation speed. We demonstrate that the Rabi frequency of a hole spin qubit in a Ge hut wire double quantum dot can be electrically tuned through the detuning energy and middle gate voltage. The discovery of an ultrafast and electrically tunable Rabi frequency in a hole spin qubit has potential applications in semiconductor quantum computing.