Quantum Discord and the Power of One Qubit
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- 5 February 2008
- journal article
- research article
- Published by American Physical Society (APS) in Physical Review Letters
- Vol. 100 (5), 050502
- https://doi.org/10.1103/physrevlett.100.050502
Abstract
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)]. 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 and the mixed ones. Although there is no entanglement between these two parts, we show that the quantum discord across this split is nonzero for typical instances of the DQC1 ciruit. Nonzero values of discord indicate the presence of nonclassical correlations. We propose quantum discord as figure of merit for characterizing the resources present in this computational model.Keywords
This publication has 18 references indexed in Scilit:
- Role of entanglement and correlations in mixed-state quantum computationPhysical Review A, 2007
- Entanglement and the power of one qubitPhysical Review A, 2005
- NMR Quantum Information ProcessingQuantum Information Processing, 2004
- Efficient Classical Simulation of Slightly Entangled Quantum ComputationsPhysical Review Letters, 2003
- On the role of entanglement in quantum-computational speed-upProceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences, 2003
- Experimental realization of Shor's quantum factoring algorithm using nuclear magnetic resonanceNature, 2001
- Separability of Very Noisy Mixed States and Implications for NMR Quantum ComputingPhysical Review Letters, 1999
- Quantum nonlocality without entanglementPhysical Review A, 1999
- Power of One Bit of Quantum InformationPhysical Review Letters, 1998
- Preface to Quantum computation: theory and experiment. Proceedings of a Discussion Meeting held at the Royal Society of London on 5 and 6 November 1997.Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences, 1998