Four-qubit device with mixed couplings.

نویسندگان

  • M Grajcar
  • A Izmalkov
  • S H W van der Ploeg
  • S Linzen
  • T Plecenik
  • Th Wagner
  • U Hübner
  • E Il'ichev
  • H-G Meyer
  • A Yu Smirnov
  • Peter J Love
  • Alec Maassen van den Brink
  • M H S Amin
  • S Uchaikin
  • A M Zagoskin
چکیده

We present the first experimental results on a device with more than two superconducting qubits. The circuit consists of four three-junction flux qubits, with simultaneous ferro- and antiferromagnetic coupling implemented using shared Josephson junctions. Its response, which is dominated by the ground state, is characterized using low-frequency impedance measurement with a superconducting tank circuit coupled to the qubits. The results are found to be in excellent agreement with the quantum-mechanical predictions.

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عنوان ژورنال:
  • Physical review letters

دوره 96 4  شماره 

صفحات  -

تاریخ انتشار 2006