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Entropy measurement of a strongly correlated quantum dot

ORAL

Abstract

The spin 1/2 entropy of electrons trapped in a quantum dot has previously been measured with great accuracy, but the protocol used for that measurement is valid only within a restrictive set of conditions. Here, we present a novel entropy measurement protocol that is universal for arbitrary mesoscopic circuits and the application of this new approach to measure the entropy of a quantum dot hybridized with a reservoir. The experimental results are compared to numerical renormalization group calculations and demonstrate a clear modification to the entropy due to Kondo correlations. For the largest couplings investigated in this work, NRG predicts a suppression of spin entropy due to the formation of a Kondo singlet. This suppression is not observed in the experiment, perhaps indicating dephasing of the Kondo singlet by the charge sensor.

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Publication: Planned Papers:<br>Entropy measurement of a strongly correlated quantum dot<br>A robust protocol for entropy measurement in mesoscopic circuits

Presenters

  • Tim J Child

    University of British Columbia

Authors

  • Tim J Child

    University of British Columbia

  • Owen I Sheekey

    University of British Columbia

  • Silvia Lüscher

    University of British Columbia

  • Saeed Fallahi

    Purdue University

  • Geoffrey C Gardner

    Purdue University, Purdue University, Microsoft Quantum Materials Lab-Purdue, West Lafayette, Indiana 47907, USA), Microsoft Quantum Materials Lab-Purdue

  • Michael J Manfra

    Department of Physics and Astronomy, Birck Nanotechnology Center, and Microsoft Quantum Lab Purdue, Purdue University, Purdue University, Purdue University, West Lafayette, Indiana 47907, USA

  • Yaakov Kleeorin

    Center for the Physics of Evolving Systems, University of Chicago, University of Chicago

  • Yigal Meir

    Ben-Gurion University of the Negev

  • Joshua Folk

    University of British Columbia