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Reducing vortex losses in superconducting microwave resonators with microsphere patterned antidot arrays

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 نشر من قبل Daniel Bothner
 تاريخ النشر 2011
  مجال البحث فيزياء
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We experimentally investigate the vortex induced energy losses in niobium coplanar waveguide resonators with and without quasihexagonal arrays of nanoholes (antidots), where large-area antidot patterns have been fabricated using self-assembling microsphere lithography. We perform transmission spectroscopy experiments around 6.25 and 12.5 GHz in magnetic field cooling and zero field cooling procedures with perpendicular magnetic fields up to B=27 mT at a temperature T=4.2 K. We find that the introduction of antidot arrays into resonators reduces vortex induced losses by more than one order of magnitude.



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