Lifting of Spin Blockade by Charged Impurities in Si-MOS Double Quantum Dot Devices

ORAL

Abstract

One obstacle that has impeded the development of electrically gated MOS singlet-triplet qubits is the lack of observed spin blockade, where the tunneling of a second electron into a dot is fast when the two-electron state is a singlet and slow when the state is a triplet, even in samples with large singlet-triplet energy splittings. We present theoretical and experimental evidence that the cause of this commonly exhibited problem in MOS double quantum dots is the presence of stray positive charges in the oxide layer that induce accidental dots near the device’s active region that allow spin blockade lifting. We also present evidence that these effects can be mitigated with device design modifications.

This work was supported by ARO (W911NF1210607, W911NF1410346, W911NF12R0012, W911NF1210609, W911NF1710257), NSF (IIA1132804, OISE1132804), the Department of Defense under Contract No. H9823015C 0453, and MINECO (Spain) FIS201233521 and FIS201564654P. The authors acknowledge support from the Vannevar Bush Faculty Fellowship program sponsored by the Basic Research Office of the Assistant Secretary of Defense for Research and Engineering and funded by the Office of Naval Research through grant N000141510029.

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Presenters

  • Cameron King

    Department of Physics, University of Wisconsin - Madison

Authors

  • Cameron King

    Department of Physics, University of Wisconsin - Madison

  • Joshua Schoenfield

    Department of Physics and Astronomy, University of California at Los Angeles

  • Maria Calderon

    Instituto de Ciencia de Materiales de Madrid, ICMM-CSIC, CSIC

  • Belita Koiller

    Instituto de Fisica, Universidade Federal do Rio de Janeiro, Univ Fed Rio de Janeiro

  • Andre Saraiva

    Instituto de Fisica, Universidade Federal do Rio de Janeiro, Univ Fed Rio de Janeiro

  • Xuedong Hu

    Department of Physics, University at Buffalo, SUNY, State NY Buffalo, Physics Department, State Univ of NY - Buffalo, University at Buffalo, State University of New York

  • HongWen Jiang

    Physics & Astronomy, Univ of California - Los Angeles, Univ of California - Los Angeles, Department of Physics and Astronomy, University of California at Los Angeles

  • Mark Friesen

    Physics, University of Wisconsin-Madison, Univ of Wisconsin, Madison, University of Wisconsin-Madison, Department of Physics, Univ of Wisconsin, Madison, Department of Physics, University of Wisconsin - Madison, Department of Physics, University of Wisconsin-Madison, Physics, Univ of Wisconsin, Madison

  • Susan Coppersmith

    Physics, University of Wisconsin-Madison, Univ of Wisconsin, Madison, University of Wisconsin-Madison, Physics, University of Wisconsin: Madison, Department of Physics, Univ of Wisconsin, Madison, Department of Physics, University of Wisconsin - Madison, Department of Physics, University of Wisconsin-Madison, Physics, Univ of Wisconsin, Madison