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Quasiparticle trapping by orbital effect in a hybrid superconducting-semiconducting circuit

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 نشر من قبل Willemijntje Uilhoorn
 تاريخ النشر 2021
  مجال البحث فيزياء
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The tunneling of quasiparticles (QPs) across Josephson junctions (JJs) detrimentally affects the coherence of superconducting and charge-parity qubits, and is shown to occur more frequently in magnetic fields. Here we demonstrate the parity lifetime to survive in excess of 50$,mathrm{mu}$s in magnetic fields up to 1$,$T, utilising a semiconducting nanowire transmon to detect QP tunneling in real time. We exploit gate-tunable QP filters and find magnetic-field-enhanced parity lifetimes, consistent with increased QP trapping by the ungated nanowire due to orbital effects. Our findings highlight the importance of QP trap engineering for building magnetic-field compatible hybrid superconducting circuits.



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