Quantum discord and the power of one qubit.

@article{Datta2008QuantumDA,
  title={Quantum discord and the power of one qubit.},
  author={Animesh Datta and Anil Shaji and Carlton M. Caves},
  journal={Physical review letters},
  year={2008},
  volume={100 5},
  pages={
          050502
        }
}
We use quantum discord to characterize the correlations present in the model called deterministic quantum computation with one quantum bit (DQC1), introduced by Knill and Laflamme [Phys. Rev. Lett. 81, 5672 (1998)10.1103/PhysRevLett.81.5672]. The model involves a collection of qubits in the completely mixed state coupled to a single control qubit that has nonzero purity. The initial state, operations, and measurements in the model all point to a natural bipartite split between the control qubit… 

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