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 and middle gate voltage (V_M). f_Rabi gradually decreases with increasing detuning energy; on the contrary, f_Rabi is positively correlated with V_M. We attribute our results to the change of electric field on SOI and the contribution of the excited state in quantum dots to f_Rabi. We further demonstrate an ultrafast f_Rabi exceeding 1.2 GHz, which evidences the strong SOI in our device. The discovery of an ultrafast and electrically tunable f_Rabi in a hole spin qubit has potential applications in semiconductor quantum computing.
@article{arxiv.2304.14846,
title = {Ultrafast and Electrically Tunable Rabi Frequency in a Germanium Hut Wire Hole Spin Qubit},
author = {He Liu and Ke Wang and Fei Gao and Jin Leng and Yang Liu and Yu-Chen Zhou and Gang Cao and Ting Wang and Jianjun Zhang and Peihao Huang and Hai-Ou Li and Guo-Ping Guo},
journal= {arXiv preprint arXiv:2304.14846},
year = {2023}
}