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Four-qubit device with mixed couplings

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 نشر من قبل Alec Maassen van den Brink
 تاريخ النشر 2005
  مجال البحث فيزياء
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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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