Spin Readout of a CMOS Quantum Dot by Gate Reflectometry and Spin-Dependent Tunneling

ORAL

Abstract

We report the measurement of the electron spin orientation in a singly-occupied gate-defined quantum dot, fabricated using CMOS compatible processes at the 300 mm wafer-scale [1]. For readout, we employ spin-dependent tunnelling [2] combined with a low-footprint single-lead quantum dot charge sensor, measured using radiofrequency gate reflectometry [3]. We demonstrate spin readout, obtaining valley splittings in the range 0.5-0.7 meV and a maximum electron spin relaxation time (T1) of 9 ± 3 s at 1 Tesla. These long lifetimes indicate that the silicon nanowire geometry and fabrication processes possess considerable promise for qubit devices, while this spin-readout method is well-suited to scalable architectures. We will discuss progress towards integrating such spin-readout with quantum-limited amplifiers [4].

[1] Nat. Commun. 7, 13575 (2016)
[2] Nature 430, 431 (2004)
[3] Nat. Commun. 6, 6084 (2015)
[4] Phys. Rev. Lett. 124, 67701 (2020)

*We acknowledge the European Union’s Horizon 2020 research and innovation programme (688539), the Engineering and Physical Sciences Research Council (EP/L015242/1), QUES2T (EP/N015118/1) and the Hub in Quantum Computing and Simulation (EP/T001062/1).

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Presenters

  • Virginia Ciriano-Tejel

    • London Centre for Nanotechnology, University College London, London WC1H 0AH, United Kingdom; Quantum Motion Technologies, Nexus, Discovery Way, Leeds, LS2 3AA, United Kingdom

Authors

  • Virginia Ciriano-Tejel

    • London Centre for Nanotechnology, University College London, London WC1H 0AH, United Kingdom; Quantum Motion Technologies, Nexus, Discovery Way, Leeds, LS2 3AA, United Kingdom

  • Michael A. Fogarty

    • London Center Nanotechnology
    • University College London, Quantum Motion Technologies
    • London Centre for Nanotechnology, University College London, London WC1H 0AH, United Kingdom; Quantum Motion Technologies, Nexus, Discovery Way, Leeds, LS2 3AA, United Kingdom

  • Simon Schaal

    • London Centre for Nanotechnology, University College London, London WC1H 0AH, United Kingdom; Quantum Motion Technologies, Nexus, Discovery Way, Leeds, LS2 3AA, United Kingdom

  • Louis HUTIN

    • CEA/LETI-MINATEC, CEA-Grenoble
    • CEA Leti
    • CEA, Grenoble
    • CEA, LETI, Minatec Campus, F-38054 Grenoble, France

  • Benoit Bertrand

    • Leti, CEA
    • CEA/LETI-MINATEC, CEA-Grenoble
    • CEA, Grenoble
    • CEA, LETI, Minatec Campus, F-38054 Grenoble, France

  • Lisa A. Ibberson

    • Hitachi Cambridge Laboratory
    • Hitachi Cambridge Laboratory, University of Cambridge
    • Hitachi Cambridge Laboratory, J.J. Thomson Avenue, Cambridge CB3 0HE, United Kingdom

  • M Fernando Gonzalez-Zalba

    • Quantum Motion Technologies
    • Hitachi Cambridge Laboratory
    • Hitachi Cambridge Laboratory, University of Cambridge
    • Quantum Motion Technologies, Nexus, Discovery Way, Leeds, LS2 3AA, United Kingdom

  • Jing LI

    • Université Grenoble Alpes, CEA, IRIG, MEM/L_Sim
    • Univ. Grenoble Alpes, CEA, IRIG-MEM-L Sim, F-38000, Grenoble, France
    • CEA, LETI, Minatec Campus, F-38054 Grenoble, France

  • Yann-Michel Niquet

    • Université Grenoble Alpes, CEA, IRIG, MEM/L_Sim
    • Univ. Grenoble Alpes, CEA, IRIG-MEM-L Sim, F-38000, Grenoble, France
    • Université Grenoble Alpes, CEA, IRIG, MEM-L Sim, F-38000 Grenoble, France

  • Maud Vinet

    • Leti, CEA
    • CEA/LETI-MINATEC, CEA-Grenoble
    • CEA Leti
    • CEA, Grenoble
    • CEA, LETI, Minatec Campus, F-38054 Grenoble, France

  • John J. L. Morton

    • University College London
    • London Center Nanotechnology
    • London Centre for Nanotechnology, University College London
    • University College London, Quantum Motion Technologies
    • London Centre for Nanotechnology, University College London, London WC1H 0AH, United Kingdom; Quantum Motion Technologies, Nexus, Discovery Way, Leeds, LS2 3AA, United Kingdo