Jirovec, DanielIST Austria; Hofmann, Andrea CIST Austria; Ballabio, Andrea; Mutter, Philipp M.; Tavani, Giulio; Botifoll, Marc; Crippa, AlessandroIST Austria; Kukucka, JosipIST Austria; Sagi, OliverIST Austria; Martins, FredericoIST Austria; Saez Mollejo, JaimeIST Austria; Prieto Gonzalez, IvanIST Austria
Spin qubits are considered to be among the most promising candidates for building a quantum processor. Group IV hole spin qubits have moved into the focus of interest due to the ease of operation and compatibility with Si technology. In addition, Ge offers the option for monolithic superconductor-semiconductor integration. Here we demonstrate a hole spin qubit operating at fields below 10 mT, the critical field of Al, by exploiting the large out-of-plane hole g-factors in planar Ge and by encoding the qubit into the singlet-triplet states of a double quantum dot. We observe electrically controlled X and Z-rotations with tunable frequencies exceeding 100 MHz and dephasing times of 1μs which we extend beyond 15μs with echo techniques. These results show that Ge hole singlet triplet qubits outperform their electronic Si and GaAs based counterparts in speed and coherence, respectively. In addition, they are on par with Ge single spin qubits, but can be operated at much lower fields underlining their potential for on chip integration with superconducting technologies.
This research was supported by the Scientific Service Units of Institute of Science and Technology (IST) Austria through resources provided by the Miba Machine Shop and the nanofabrication facility, and was made possible with the support of the NOMIS Foundation. This project has received funding from the European Union’s Horizon 2020 research and innovation programme under Marie Sklodowska-Curie grant agreements no. 844511 and no. 75441, and by the Austrian Science Fund FWF-P 30207 project. A.B. acknowledges support from the European Union Horizon 2020 FET project microSPIRE, no. 766955. M. Botifoll and J.A. acknowledge funding from Generalitat de Catalunya 2017 SGR 327. The Catalan Institute of Nanoscience and Nanotechnology (ICN2) is supported by the Severo Ochoa programme from the Spanish Ministery of Economy (MINECO) (grant no. SEV-2017-0706) and is funded by the Catalonian Research Centre (CERCA) Programme, Generalitat de Catalunya. Part of the present work has been performed within the framework of the Universitat Autónoma de Barcelona Materials Science PhD programme. Part of the HAADF scanning transmission electron microscopy was conducted in the Laboratorio de Microscopias Avanzadas at Instituto de Nanociencia de Aragon, Universidad de Zaragoza. ICN2 acknowledge support from the Spanish Superior Council of Scientific Research (CSIC) Research Platform on Quantum Technologies PTI-001. M.B. acknowledges funding from the Catalan Agency for Management of University and Research Grants (AGAUR) Generalitat de Catalunya formation of investigators (FI) PhD grant.
Jirovec D, Hofmann AC, Ballabio A, et al. A singlet triplet hole spin qubit in planar Ge. Nature Materials. 2021;20(8):1106–1112. doi:10.1038/s41563-021-01022-2
Jirovec, D., Hofmann, A. C., Ballabio, A., Mutter, P. M., Tavani, G., Botifoll, M., … Katsaros, G. (2021). A singlet triplet hole spin qubit in planar Ge. Nature Materials. Springer Nature. https://doi.org/10.1038/s41563-021-01022-2
Jirovec, Daniel, Andrea C Hofmann, Andrea Ballabio, Philipp M. Mutter, Giulio Tavani, Marc Botifoll, Alessandro Crippa, et al. “A Singlet Triplet Hole Spin Qubit in Planar Ge.” Nature Materials. Springer Nature, 2021. https://doi.org/10.1038/s41563-021-01022-2.
D. Jirovec et al., “A singlet triplet hole spin qubit in planar Ge,” Nature Materials, vol. 20, no. 8. Springer Nature, pp. 1106–1112, 2021.
Jirovec D, Hofmann AC, Ballabio A, Mutter PM, Tavani G, Botifoll M, Crippa A, Kukucka J, Sagi O, Martins F, Saez Mollejo J, Prieto Gonzalez I, Borovkov M, Arbiol J, Chrastina D, Isella G, Katsaros G. 2021. A singlet triplet hole spin qubit in planar Ge. Nature Materials. 20(8), 1106–1112.
Jirovec, Daniel, et al. “A Singlet Triplet Hole Spin Qubit in Planar Ge.” Nature Materials, vol. 20, no. 8, Springer Nature, 2021, pp. 1106–1112, doi:10.1038/s41563-021-01022-2.
All files available under the following license(s):
This Item is protected by copyright and/or related rights. [...]
Link(s) to Main File(s)
Material in IST:
Dissertation containing IST record
News on IST Homepage