Decoherence of up to 8-qubit entangled states in a 16-qubit superconducting quantum processor

  title={Decoherence of up to 8-qubit entangled states in a 16-qubit superconducting quantum processor},
  author={A. Ozaeta and P. McMahon},
  journal={arXiv: Quantum Physics},
We report on the coherence of Greenberger-Horne-Zeilinger (GHZ) states comprised of up to 8 qubits in the IBM ibmqx5 16-qubit quantum processor. In particular, we evaluate the coherence of GHZ states with $N=1,\ldots,8$ qubits, as a function of a delay time between state creation and measurement. We find that the decay in coherence occurs at a rate that is linear in the number of qubits. This is consistent with a model in which the dominant noise affecting the system is uncorrelated across… Expand

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