Silvano De Franceschi

B. Brun¹, S. Zihlmann¹, N. Piot¹, C. Yu¹, V. Schmitt¹, J.C. Abadillo-Uriel², V. P. Michal², H. Niebojewski³, B. Bertrand³, L. Hutin³, M. Vinet³, M. Filippone², Y.-M. Niquet², E. Dumur¹, X. Jehl¹, R. Maurand¹, and S. De Franceschi¹

¹Univ. Grenoble Alpes, CEA, Grenoble INP, IRIG-PHELIQS-LaTEQS, Grenoble, France 
²Univ. Grenoble Alpes, CEA, IRIG-MEM-L_Sim, Grenoble, France
³Univ. Grenoble Alpes, CEA, LETI, Minatec Campus, F-38000 Grenoble, France 

https ://www.quantumsilicon-grenoble.eu ; https://www.lateqs.fr

Owing to their intrinsic spin-orbit coupling, hole spin qubits are responsive to electric field excitation. This can allow for efficient electrically-driven spin control as well as for spin cavity quantum electrodynamics, thereby opening interesting prospects for qubit control, readout, and long-range coupling. Spin-electric susceptibility, however, renders hole qubits generally vulnerable to electrical noise, which limits their coherence time. Here we investigate the coherence properties of a single hole electrostatically confined in a natural silicon metal-oxide-semiconductor device made using an industry-compatible fabrication process. By varying the magnetic field orientation, we reveal the existence of operation sweet spots where the impact of charge noise is minimized while preserving an efficient electric-dipole spin control. We correspondingly observe an extension of the Hahn-echo coherence time up to 88 μs, exceeding by an order of magnitude the best reported values for hole- spin qubits, and approaching the state-of-the-art for electron-spin qubits with synthetic spin-orbit coupling in isotopically-purified silicon. This finding largely enhances the prospects of silicon-based hole spin qubits for scalable quantum information processing.