Resolving the positions of defects in superconducting quantum bits

  title={Resolving the positions of defects in superconducting quantum bits},
  author={Alexander Bilmes and Anthony Megrant and Paul V. Klimov and Georg Weiss and John M. Martinis and Alexey V. Ustinov and J{\"u}rgen Lisenfeld},
  journal={Scientific Reports},
Solid-state quantum coherent devices are quickly progressing. Superconducting circuits, for instance, have already been used to demonstrate prototype quantum processors comprising a few tens of quantum bits. This development also revealed that a major part of decoherence and energy loss in such devices originates from a bath of parasitic material defects. However, neither the microscopic structure of defects nor the mechanisms by which they emerge during sample fabrication are understood. Here… 

Probing defect densities at the edges and inside Josephson junctions of superconducting qubits

Tunneling defects in disordered materials form spurious two-level systems which are a major source of decoherence for micro-fabricated quantum devices. For superconducting qubits, defects in tunnel

Quantum defects from single surface exhibit strong mutual interactions

  • Chih-Chiao HungTim KohlerK. Osborn
  • Physics
  • 2023

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