Non-universal transmission phase behaviour of a large quantum dot

ORAL

Abstract

The electron wave function experiences a phase modification at coherent transmission through a quantum dot. This transmission phase undergoes a characteristic shift of π when scanning through a Coulomb blockade resonance. Between successive resonances either a transmission phase lapse of π or a phase plateau is theoretically expected to occur depending on the parity of quantum dot states. Despite considerable experimental effort, this transmission phase behaviour has remained elusive for a large quantum dot1. Here we report on transmission phase measurements across such a large quantum dot hosting hundreds of electrons. Scanning the transmission phase along fourteen successive resonances with an original two-path interferometer, we observe both phase lapses and plateaus. We demonstrate that quantum dot deformation alters the sequence of phase lapses and plateaus via parity modifications of the involved quantum dot states2. Our findings set a milestone towards a comprehensive understanding of the transmission phase of quantum dots.

1. Schuster et al. Nature (1997)
2. Edlbauer et al. Nat. Commun. (2017)

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Presenters

  • Hermann Edlbauer

    Institute Néel, Centre national de la recherche scientifique (CNRS)

Authors

  • Hermann Edlbauer

    Institute Néel, Centre national de la recherche scientifique (CNRS)

  • Shintaro Takada

    Natl Inst of Adv Indust Sci &Tech, CNRS, Institut Néel, National Institute of Advanced Industrial Science and Technology (AIST)

  • Grégoire Roussely

    CNRS, Institut Néel, Institute Néel, Centre national de la recherche scientifique (CNRS)

  • Michihisa Yamamoto

    Department of Applied Physics, University of Tokyo, University of Tokyo, JST, PRESTO, JST, Applied Physics, University of Tokyo

  • Seigo Tarucha

    Department of Applied Physics, University of Tokyo, University of Tokyo, Department of Applied Physics, The University of Tokyo, Applied Physics, University of Tokyo, Applied Physics, The University of Tokyo

  • Arne Ludwig

    Lehrstuhl für angewandte Festkörperphysik, Ruhr-Universität Bochum, Lehrstuhl für Angewandte Festkörperphysik, Ruhr-Universität, Lehrstuhl für Angewandte Festkörperphysik, Ruhr-Universität Bochum

  • Andreas D. Wieck

    Lehrstuhl für angewandte Festkörperphysik, Ruhr-Universität Bochum, Lehrstuhl für Angewandte Festkörperphysik, Ruhr-Universität, Lehrstuhl für Angewandte Festkörperphysik, Ruhr-Universität Bochum

  • Tristan Meunier

    QUEST, Institut Neel, CNRS, Institut Néel, Institute Néel, Centre national de la recherche scientifique (CNRS)

  • Christopher Bäuerle

    QUEST, Institut Neel, CNRS, Institut Néel, Institute Néel, Centre national de la recherche scientifique (CNRS)