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Spin-polarized bound states in semiconductor-superconductor-ferromagnetic insulator islands

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 نشر من قبل Charles Marcus
 تاريخ النشر 2021
  مجال البحث فيزياء
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We report Coulomb blockade transport studies of InAs nanowires grown with epitaxial superconducting Al and ferromagnetic insulator EuS on overlapping facets. By comparing experimental results to a theoretical model, we associate cotunneling features in even-odd bias spectra with spin-polarized Andreev levels, indicating that spin splitting exceeding the induced superconducting gap at zero applied magnetic field. Energies of the polarized subgap states can be tuned on either side of zero by electrostatic gates.



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