Zero Flux Anomaly in Mesoscopic Normal Metals

ORAL

Abstract

Our recent scanning SQUID susceptometry measurements of individual mesoscopic normal metal rings found persistent currents consistent with theoretical predictions. In addition to the persistent current signal, all rings exhibited a step anomaly in the SQUID response vs flux around zero applied flux and a large paramagnetic linear susceptibility. We present the characteristics of the zero flux anomaly observed in multiple rings and thin films and explore possible explanations. Key features include a notable frequency dependence between 11 and 333 Hz and a strong spatial correlation with the large paramagnetic spin signal.

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Authors

  • Julie Bert

    Stanford University

  • Hendrik Bluhm

    Harvard University, Stanford University

  • Nicholas Koshnick

    Stanford University

  • Martin Huber

    Department of Physics, University of Colorado Denver, Departments of Physics and Electrical Engineering, University of Colorado Denver, Denver, Colorado, 80217, USA, University of Colorado Denver and NIST

  • Kathryn Moler

    Stanford University, Geballe Laboratory for Advanced Materials, Stanford University, Geballe Laboratory for Advanced Materials, Stanford University, Stanford, California, 94305, USA