Josephson phase qubit circuit for the evaluation of advanced tunnel barrier materials

نویسندگان

  • Jeffrey S Kline
  • Haohua Wang
  • Seongshik Oh
  • John M Martinis
  • David P Pappas
چکیده

We have found that crystalline Josephson junctions have problems with control of critical current density that decrease circuit yield. We present a superconducting quantum bit circuit designed to accommodate a factor of five variation in critical current density from one fabrication run to the next. The new design enables the evaluation of advanced tunnel barrier materials for superconducting quantum bits. Using this circuit design, we compare the performance of Josephson phase qubits fabricated with MgO and Al2O3 advanced crystalline tunnel barriers to AlOx amorphous tunnel barrier qubits.

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تاریخ انتشار 2008